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Copyright ’ 1988-1994, Brains software, All Rights Reserved. $$Apple Menu Using Menu Commands Menu Command Asymptote command $i$About Asymptote$i$ ± Display version, registration and copyright information $i$Help...$i$ ± Access this on-line help system $b$help$b$ ¥¥ For more information on the on-line help system, type help help in the $i$Command Window$i$ $$File Menu Using Menu Commands Menu Command Asymptote command $i$New$i$ ± Open a new Text Editor Window $b$newwindow$b$ $i$Open...$i$ ± Open an existing text file $i$Recorder$i$ ± Specify which window is the recorder ¥ See also the topic: $i$Recorder menu$i$ $i$Data$i$ ± Specify which window is the data file $b$datafile$b$ ¥ See also the topic: $i$Data menu$i$ $i$Close$i$ ± Close a window $b$closewindow$b$ $i$Save$i$ ± Save the contents of the active window to a disk file $i$Save As...$i$ ± Save the contents of the active window under a different filename $i$Graph Page Setup...$i$ ± Choose a new graph page setup $b$pagesetup$b$ ¥ See also the topic: $i$Graph Page Setup menu$i$ $i$Print Graph$i$ ± Print the contents of the $i$Graph Window$i$ $b$print$b$ $i$File Page Setup...$i$ ± Change the page setup for a Text Editor Window $i$Print File$i$ ± Print a Text Editor Window $i$Options$i$ ± Change options for Asymptote ¥ See also the help topics: $i$Options menu$i$ $i$Memory Use$i$ $i$Preferences$i$ $i$Search Paths$i$ $i$Command Macros$i$ $i$Quit$i$ $b$quit$b$ ± Quit Asymptote $$Graph Page Setup sub-menu under the File Menu Menu Command Asymptote command $i$New Page Setup...$i$ $b$pagesetup ?$b$ ± Choose a new graph page setup $i$Save to recorder$i$ ± Save the current graph page setup to the Recorder $i$Read from recorder$i$ ± Read the graph page setup from the Recorder $b$pagesetup$b$ $$Options sub-menu under the File Menu Menu Command Asymptote command $i$Preferences...$i$ ± Select your personal preferences see:$i$Preferences$i$ $i$Memory Use$i$ ± Configure how Asymptote uses memory see:$i$Memory Use$i$ $i$Search Paths File...$i$ ± Select a Search Paths File see:$i$Search Paths$i$ $i$Command Macros$i$ ± Select a command macros file see:$i$Command˚Macros$i$ $$Preferences Menu Command on the Options sub-menu To make changes to your preferences simply check or uncheck the various items and click on the OK button. Asymptote remembers your preferences until you change them again. $b$Dialog and Alert Preferences$b$ $i$Center dialog and alert boxes on screen$i$ When you select this preference, Asymptote centers dialogs and alert boxes on your screen. If you have a large screen, you may find this preference particularly helpful. Deselect this preference if you want dialog and alert boxes to appear below the menu bar instead. $i$Show note alerts$i$ From time to time Asymptote displays a note alert with non-essential information. If you donàt want to be bothered by these notes, deselect this preference. Turning off note alerts is particularly useful when running a script in the background because note alerts interrupt the execution of scripts. $i$Notify me when the Recorder stops playing in the background$i$ Select this preference if you want Asymptote to tell you when it has finished running a script in the background. The notification message looks like this: Selecting this preference is a convenient way to have Asymptote notify you when it has finished drawing your graph while running in the background. $b$Script Preferences$b$ $i$Execute the script Asymptote Startup when Asymptote starts$i$ When you select this preference, Asymptote runs the script named Asymptote Startup every time it starts up. The Asymptote Startup script is a convenient way to configure Asymptote with your personal preferences for the variables of the $i$graphics environment$i$ such as pen size, font, and fill pattern every time Asymptote starts up. For more information on the $i$Startup script$i$ see Appendix A of the Asymptote $i$User's Guide$i$. $i$Clear the Graph Window before running the Recorder script$i$ When you select this preference, Asymptote clears the $i$Graph Window$i$ every time you run the Recorder. If you deselect this preference, the new graph is drawn on top of the old graph every time you run the Recorder. If you are running the same script over and over again in order to make changes to your graph, you probably want to select this preference. If you are running several different scripts to draw multiple graphs on the same page, you probably want to deselect this preference. Remember, you can always use the clear command to clear the $i$Graph Window$i$ whenever you need a blank page. $i$Donàt update the Status and Vectors Windows$i$ The $i$Status$i$ and $i$Vectors Windows$i$ are very useful tools for debugging your scripts. You can use them to monitor changes to the $i$graphics˚environment$i$ and the values in Asymptotes vectors. But updating these windows takes time and makes your scripts take longer to run. Once you have debugged your scripts, you probably want to select this preference to make your scripts run faster. Closing the $i$Status$i$ and $i$Vectors$i$ Windows when you arenàt using them also makes your scripts run faster. ¥ Note: If you have selected this preference and want to have Asymptote update the $i$Status$i$ or $i$Vectors$i$ Windows while Asymptote is running a script, simply click the window to have Asymptote update its contents. $i$Trace the execution of scripts$i$ This preference is useful when you are debugging your scripts because you can monitor how your scripts are running. When you select this preference, Asymptote scrolls through the text in your scripts to show you which line is currently being executed. Scrolling through the text and updating windows takes time, however, so if you want your scripts to run faster, deselect this preference. $i$Add new commands at the end of the Recorder$i$ When you type commands in the Command Window or select commands from menus, Asymptote saves the command in the $i$Recorder Window$i$. When you select this preference, Asymptote saves new commands at the end of the current Recorder script. In this way, the $i$Recorder$i$ provides a history of all the commands you used to produce a graph. After youàve created a graph, you may want to add commands in the middle of your Recorder script to make changes in your graph. In this case, you may prefer to deselect this preference to have Asymptote insert new commands at the current position of the insertion point in your Recorder script. With this preference deselected, you can type commands in the Command Window or select commands from Asymptoteàs menus to have Asymptote insert them at the current insertion point in your Recorder script. ¥ Note: The order in which Asymptote executes commands is important. If you add commands in the middle of your Recorder script, be sure to run the Recorder from time to time to see if executing the commands in sequence produces the results you want. $b$Other Preferences$b$ $i$Show the graph cursor information box in the Graph Window$i$ When you issue commands that activate the graph cursor (for example, $b$moveto$b$ ? or $b$drawto$b$ ?) Asymptote activates the graph cursor. Select this preference if you want Asymptote to display information about the current position of the graph cursor in the $i$Graph Window$i$. $i$Show the names of directories being searched$i$ Asymptote searches for files it needs to open using your Search Paths file. Select this preference if you want to view the progress of the search. You may find this useful if Asymptote is unable to locate a file and you want to know what directories it has searched. If youàd rather not be bothered with the details of the search, deselect this preference. $i$Ask to save the Graph Windowàs contents when it is closed$i$ Select this preference if you want to save your graph to a PICT file every time you close the $i$Graph Window$i$. For most circumstances, you donàt need to save the graph because your Recorder script provides a complete record of how your graph was made. You can always run the Recorder to generate your graph again, but if you would like to have PICT versions of all your graphs, select this preference. When you select this preference, Asymptote asks you if you want to save the contents of the $i$Graph Window$i$ if you close the $i$Graph Window$i$ without saving the graph to a PICT file first. You may want to save your graphs to PICT files if you want to use them in other programs or if you are creating complicated graphics that take a long time to draw from a script. ¥ Note: You can save the current contents of the $i$Graph Window$i$ to a PICT file at anytime by clicking the $i$Graph Window$i$ and selecting File Save˚As. $i$Use the maximum printer resolution for the highest quality graphics$i$ Select this preference if you want Asymptote to draw your graph on a high resolution coordinate grid. A high resolution grid (one with more dots per inch) produces the highest quality output on your printer. If you are creating graphs to use in another application, you may need to experiment with the setting of this preference. Most drawing and desktop publishing programs can handle the high resolution graphics Asymptote produces when you select this preference, but others cannot. If you have difficulty reading or pasting an Asymptote graph into another program, try deselecting this preference. $$Memory Use menu command on the Options sub-menu To configure how Asymptote uses memory, select the $i$Memory Use$i$ item from the $i$Options$i$ menu. A dialog box lets you choose what settings Asymptote should use the next time you launch it. Here you can select how long to make Asymptote's vectors and how many registers and stack elements you want. For a detailed description of the Memory Use dialog, see Chapter 3 of the Asymptote $i$User's Guide$i$. WOULD YOU LIKE TO PLOT MORE POINTS? Use the $i$Memory Use$i$ dialog box to lengthen Asymptote's x, y, p, or e vectors so you can plot more points. The next time Asymptote starts, it allocates additional memory for the increased size of the data arrays. If there isn't enough memory to accommodate the larger vectors, Asymptote makes them as long as possible. IS MEMORY LOW? If you find you are running low on memory try the following steps: ¥ Close windows you are not using and save their contents. ¥ On color Macintoshes, use the Monitors Control Panel to switch to 1 bit. ¥ Allocate more memory to Asymptote in the Finder as described in the section titled ¼Using Memory½ of the $i$User's Guide$i$. ¥ Select File>Options>Memory Use and reduce the number of registers you are using, or the depth of the vector calculator stack. Note: If the amount of free memory is getting low, Asymptote does not maintain a snapshot of the $i$Graph Window$i$. If this happens, the $i$Graph Window$i$ may take much longer to be drawn. Free up some memory to improve performance. ¥ Note: The $i$Status Window$i$ presents some useful information about your usage of memory. $$Search Paths menu command on the Options menu Asymptoteàs search paths lets you specify where Asymptote should look when it needs to open a script or a data file. You store these paths in a Search Paths File. When Asymptote needs to locate a file to open, it automatically searches the paths for you. To create a Search Paths File, type a set of search paths (one per line) into a Text Editor Window and save the file in the same directory as Asymptote. Then, select File>Options>Search Paths File which tells Asymptote to use the new file. You can change your search paths at any time by opening the Search Paths file in a Text Editor Window. If you have the current Search Paths file open in a Text Editor Window, Asymptote uses the edited copy (rather than the one on disk) for the search paths. When Asymptote needs to open a file, it first looks in the Asymptote folder or in the System Folder. If Asymptote canàt find the file, it uses the search paths in the current Search Paths File to locate the file. The Search Paths File is a list of places in which Asymptote looks for files. Each line of the Search Paths File is a possible ¾path nameà that identifies a particular file or group of files in your hard disk. You can define either full or partial path names. Full path names begin with the name of the disk to search. You can use them to locate a file on any disk in your Macintosh desktop. Partial path names, which begin with a colon, specify files or folders in the Asymptote folder. For example, if a file named ¾MyDataà is in a folder named ¾Testing,à which is in the same folder as Asymptote, the partial path name of the file would be the following: :Testing:MyData If the Asymptote folder were on a hard disk named ¾Smith,à the full path name to the same file might be something like this: Smith:Asymptote:Testing:MyData $b$Using Wild Cards in the Search Paths File$b$ The above examples specified search paths that matched files exactly. To specify a search path that can locate any number of files in any number of directories, use the special characters, question mark (?) and asterisk (*). A question mark in a path name matches any single character. An asterisk matches any number of characters. For example, the search path Smith:Asymptote:Testing:MyData?? matches any file in the folder Smith:Asymptote:Testing with the name MyData followed by any two characters. To locate files named MyData followed by any number of characters, you could use the search path Smith:Asymptote:Testing:MyData* or you could match any file in the directory Smith:Asymptote:Testing:MyData with the search path Smith:Asymptote:Testing:* Replace the name of a folder in a search path with a * to have Asymptote include that folder and all of the folders inside it in the search path. This gives you a powerful way to search whole directory trees for files. If you replace the disk name in a search path with an asterisk, Asymptote searches all the disks on the desktop. Here are some examples: Files with names ending in ¾.datà in the folder ¾My Data:Julyà on the disk ¾Data˚1à: Data 1:My Data:July:*.dat Files ending in ¾.datà in any folder inside the folder ¾My Dataà: Data 1:My Data:*:*.dat Files ending in ¾.datà in any folder on the disk ¾Data˚1à: Data 1:*:*.dat Any file ending in ¾.datà on any disk on the desktop. *:*.dat Files beginning with the letters ¾abcà in the Asymptote folder: :abc* Files beginning with the letters ¾absà in any folder in the Asymptote folder: :*:abc* All files in the Asymptote folder and all of the folders inside it: :*:* Files beginning with the letter ¾zà in any folder that has ¾xyà as its third and fourth characters followed by any number of characters: :??xy*:z* $$Command Macros File menu command on the Options sub-menu Command macros are powerful way to streamline and configure Asymptote to suit you and your needs. When Asymptote begins processing a new command, either when it reads the next line of a script or when you type a command in the $i$Command Window$i$, it first searches the Command Macros File to see if there is a macro with the given name. If a macro is found it replaces the macro name with macro definition leaving the rest of the command unchanged. If a macro is not found, Asymptote searches for a script with the same name as the command using the current search paths (see $i$Search Paths$i$). To choose the file you would like Asymptote to use for command macros, select the $i$Command Macros$i$ menu command from the $i$Options$i$ menu. Asymptote asks you to select the macros file and uses that file until you select a new one. WRITING COMMAND MACROS: A command macro must have the name of the macro as the first item in the line. The text of the macro should follow after that. The text of the line can contain arguments (&1, &2, &3, etc). For example, the following macro: stars pointsymbol 5 filled sets the point style to filled 5 pointed stars every time you type 'stars' in the $i$Command Window$i$ or whenever the command 'stars' is encountered in a script. Take a look at the file ¼Asymptote Macrosà for some examples. COMMAND MACROS AS ONE LINE SCRIPTS: Command macros can also accept arguments. For example the following macro in the command macros file: solidpts pointsymbol &1 filled sets the pointsymbol to filled squares if you type: solidpts 4 in the Command Window or in another script. Its sets the point style to filled triangles if you use: solidpts 3 instead. In this case the single argument to the macro ¾solidptsà is the number of sides of the point. USING COMMAND MACROS TO REDEFINE ASYMPTOTE COMMANDS: Another way to use command macros is to redefine Asymptote's commands to suit your tastes. You may not like the name of a particular command, you may want to shorten a command so it is easier to type, or you may want to customize Asymptote commands to look more like commands you are familiar with from other programs. For example, to redefine the graphlimits command to be 'gl' use the macro: gl graphlimits Then the command gl 1 10 -1 10 has exactly the same effect as: graphlimits 1 10 -1 10 and it is much shorter to type. ¥ Note: You can open and edit the Command Macros file while you are using Asymptote. As you make changes to the macros, Asymptote will use the new definitions when it executes a macro. There is no need to save the macros file and restart Asymptote (the same is true for the Search Paths file, but not for the Help file). $$Edit Menu Using Menu Commands Menu Command Asymptote command $i$Undo...$i$ ± Undo the last change you made in a Text Editor Window $i$Cut...$i$ ± Cut the selected text to the clipboard $i$Copy...$i$ ± Copy the selected text to the clipboard or ± Copy the contents of the $i$Graph Window$i$ to the clipboard $i$Paste...$i$ ± Paste the clipboard text at the insertion point $i$Clear...$i$ ± Clear selected text or ± Clear the $i$Graph Window$i$ $b$clear$b$ $i$Create Publisher$i$ ± Create a new publisher of the $i$Graph Window$i$ $b$publish$b$ $i$Subscribe To...$i$ ± Open a text edition in a Text Editor Window $b$open$b$ $i$Publisher/Subscriber Options...$i$ ± Set the options for a publisher or subscriber $$Search sub-menu under the Edit Menu Menu Command Search Menu:$i$ $i$Find...$i$ ± Search from some text in one or more text files $i$Find Again$i$ ± Find the next occurrence of the search text $i$Find in Next File$i$ ± Open the next file and find the next occurrence of the search text $$Replace sub-menu under the Edit Menu Menu Command $i$Selection$i$ ± Replace the selected text with the replacement text $i$and Find Again$i$ ± Replace the selected text and search again $i$All$i$ ± Replace all occurrences of the search text with the replacement text $$Go to sub-menu under the Edit Menu $i$Top$i$ ± Move the insertion point to the first line of a Text Editor Window $i$Bottom$i$ ± Move the insertion point to the last line of a Text Editor Window $i$Line #...$i$ ± Move the insertion point to a specified line number in a Text Editor Window $$Indent sub-menu under the Edit Menu $i$Left$i$ ± Indent the selected text to the left by one tab stop $i$Right$i$ ± Indent the selected text to the right by one tab stop $$Configure sub-menu under the Edit Menu $i$Font$i$ ± Choose a font for a Text Editor Window $i$Font Size$i$ ± Choose a font size for a Text Editor Window $i$Tab width...$i$ ± Choose the width for a Text Editor Window $i$Auto indent$i$ ± Auto indent when you press the Return key $$Data Menu Using Menu Commands Menu Command Asymptote command $i$Lines...$i$ ± Select which of the data file to use when reading data $b$datalines$b$ $i$Columns...$i$ ± Select the columns of the data file to read $b$datacolumns$b$ $i$Read x data...$i$ ± Read a row of the data file into the x vector $b$readrow$b$ x ± Read a column of the data file into then x vector $b$readcolumn$b$ x $i$Read y data...$i$ ± Read a row of the data file into the y vector $b$readrow$b$ y ± Read a column of the data file into the y vector $b$readcolumn$b$ y $i$Read point styles...$i$ ± Read a row of the data file into the p vector $b$readrow$b$ p ± Read a column of the data file into the p vector $b$readcolumn$b$ p $i$Read e data...$i$ ± Read a row of the data file into the error vector $b$readrow$b$ e ± Read a column of the data file into the e vector $b$readcolumn$b$ e $i$Read labels...$i$ ± Read a row of the data file into the l vector $b$readrow$b$ l ± Read a column of the data file into the l vector $b$readcolumn$b$ l $i$Sort by X$i$ ± Sort all the vectors by the x vector $b$sort$b$ $i$Calculate...$i$ ± Activate the rpn calculator window $b$rpn$b$ $i$Bin X...$i$ ± Calculate the histogram of the values in the x vector $b$binxy$b$ $i$Smooth Y...$i$ ± Smooth the y data with a variable width window $b$smooth$b$ $i$Spline Y = f(x)...$i$ ± Fit a spline to the x,y data points $b$spline$b$ $i$Fit Y = a + b*X...$i$ ± Fit a polynomial to the x,y data $b$fit$b$ $i$# of points...$i$ ± Set the lengths of the x,y,e,p, l vectors $b$npts$b$ $$Set Menu Using Menu Commands Menu Command Asymptote command $i$Graph$i$ ± Set the x and y limits of the graph frame $b$graphlimits$b$ ± Set the spacing of axis tick marks $b$graphticks$b$ ± Set the position of the graph in the page $b$graphframe$b$ ± Set the aspect ratio of the graph on the page $b$graphaspect$b$ $i$Pen$i$ ± Set the pen: size $b$pensize$b$ color $b$pencolor$b$ transfer mode $b$penmode$b$ pattern $b$penpattern$b$ dash pattern $b$pendash$b$ $i$Background ± Choose a background color for the $i$Graph Window$i$ $b$backcolor$b$ $i$Fill pattern$i$ ± Set the fill pattern for points and polygons $b$fillpattern$b$ $i$Point Symbol$i$ ± Set the symbol to draw at each point $b$pointsymbol$b$ $i$Point Size$i$ ± Set default size for point symbols $b$pointsize$b$ $i$Tick Size$i$ ± Set the default size for major tick marks $b$ticksize$b$ $i$Scale Factor$i$ ± Set the scale factor for points, tick marks and text $b$scale$b$ $i$Rotation$i$ ± Set the rotation angle of the graphics environment $b$rotation$b$ $i$Font$i$ ± Change the font for the $i$Graph Window$i$ $b$fontname$b$ $i$Font Size$i$ ± Set the default size for labels $b$fontsize$b$ $i$Text Mode$i$ ± Set the transfer mode for text $b$textmode$b$ $i$Notation$i$ ± Set the notation format for labels and tick marks $b$notation$b$ $i$Digits$i$ ± Set how many digits to use for labels and ticks $b$digits$b$ $i$Variable$i$ ± Set or change the value of a variable $b$set$b$ $$Plot Menu Using Menu Commands Menu Command Asymptote command $i$Clear...$i$ ± Clear the graph $b$clear$b$ $i$Zoom In/Out$i$ ± Zoom the graph to show more or less detail $b$zoomgraph$b$ $i$Show Graph$i$ ± Zoom to show the graph frame $b$showgraph$b$ $i$Show Page$i$ ± Zoom to show the entire page $b$showpage$b$ $i$Full Screen$i$ ± Turn full screen mode on and off $b$fullscreen$b$ $i$Cursor$i$ ± Activate the graph cursor $b$cursor$b$ $i$Points$i$ ± Plot the x,y data as individual points $b$plotpoints$b$ $i$Errors$i$ ± Plot error bars on the x,y points $b$ploterrors$b$ $i$Line$i$ ± Plot the x,y data a line $b$plotline$b$ $i$Arrows$i$ ± Plot arrows between pairs of points $b$plotarrows$b$ $i$Histogram$i$ ± Plot the x,y data as a histogram $b$plothistogram$b$ $i$Polygon$i$ ± Connect the x,y points to make a polygon $b$plotpolygon$b$ $i$Labels...$i$ ± Plot labels at each of the x,y data points $b$plotlabels$b$ $$Draw Menu Using Menu Commands Menu Command Asymptote command $i$Frame...$i$ ± Draw a frame around the graph $b$drawframe$b$ $i$Grid...$i$ ± Draw grid lines $b$drawgrid$b$ $i$Axis...$i$ ± Draw an axis on one side of the graph frame $b$drawaxis$b$ $i$Title...$i$ ± Draw a title centered above the graph frame $b$drawtitle$b$ $i$X Label...$i$ ± Draw a label on the x axis of the graph $b$drawxlabel$b$ $i$Y Label...$i$ ± Draw a label on the y axis of the graph $b$drawylabel$b$ $i$Label...$i$ ± Draw a label at the current pen position $b$drawlabel$b$ $i$Move to...$i$ ± Move the pen to a new x,y location $b$moveto$b$ $i$Draw to...$i$ ± Draw a line from the current pen position to a new x,y position $b$drawto$b$ $i$Arrow to...$i$ ± Draw an arrow from the current pen position to a new x,y position $b$drawarrowto$b$ $i$Point$i$ ± Draw a point on the graph $b$drawpoint$b$ $i$Clip To Frame$i$ ± Select whether to allow drawing outsize the graph frame or not $b$cliptoframe$b$ $$Window Menu Using Menu Commands Menu Command Asymptote command $i$Graph$i$ ± Bring the $i$Graph Window$i$ to the top $i$Command$i$ ± Bring the Command Window to the top $i$Calculator$i$ ± Bring the RPN window to the top $b$rpn$b$ $i$Vectors$i$ ± Bring the vectors window to the top $i$Variables$i$ ± Bring the variables window to the top $i$Status$i$ ± Bring the status window to the top $i$Help$i$ ± Bring this help window to the top $b$help$b$ ¥ Use the other items on this menu to select a file in a Text Editor Window. $$Script Menu Using Menu Commands Menu Command Asymptote command $i$Run Recorder$i$ ± Start executing the current $i$Recorder Window$i$ $b$run$b$ $i$Run Active Window$i$ ± Run the script in the active window $i$Run Selection$i$ ± Run selected lines in the active window $i$Pause$i$ ± Pause on the currently executing command $b$pause$b$ $i$Step$i$ ± Execute the next command in the current script $i$Stop$i$ ± Stop running a script $b$stop$b$ $i$Trace$i$ ± Trace the execution of scripts as they execute $b$trace$b$ $i$Trace$i$ ± Trace the execution of scripts as they execute $b$trace$b$ $i$Add Commands$i$ ± Select whether to add commands at the end of the $i$Recorder Window$i$ or at the insertion point ¥ See also:$i$Preferences$i$ $$Movie Menu Using Menu Commands Menu Command Asymptote command $i$New...$i$ ± Create a new, empty movie in the $i$Movie Window$i$ $b$moviefile$b$ $i$Open...$i$ ± Open an existing movie file in the $i$Movie Window$i$ $b$moviefile$b$ $i$Add Frame$i$ ± Copy the $i$Graph Window$i$ to a new movie frame $b$movieframe$b$ $i$Loop$i$ ± Repeat the movie when it finishes playing $i$Loop Back and Forth$i$ ± Reverse the movie when it finishes playing $i$Faster$i$ ± Increase the speed of the movie $i$Slower$i$ ± Decrease the speed of the movie $$Recorder Menu sub-menu under the File Menu Menu Command Asymptote command $i$New Recorder...$i$ ± Open a new Text Editor and make it the Recorder $i$Open As Recorder...$i$ ± Open an existing text file and make it the Recorder $b$recorder$b$ To make a different window to be the recorder, simply select its name on this menu. ¥ The current $i$Recorder Window$i$ (if any) has a microphone icon next to its name. See also:$i$Recorder Window$i$ $$Data sub-menu under the File Menu Menu Command Asymptote command $i$New Data...$i$ ± Open a new window as the $i$Data Window$i$ $i$Open As Data...$i$ ± Open an existing text file and make it $b$datafile$b$ the $i$Data Window$i$ To make a different window to be the $i$Data Window$i$, simply select its name on this menu. ¥ The current $i$Data Window$i$ (if any) has an icon with the numbers 1,2,3 next to its name. See also:$i$Data Window$i$ $$Recorder Window Asymptote Windows The Recorder is a special text editing window that logs all the commands you use to make your graph. As you work in Asymptote, whether you are selecting menu commands or typing commands, the $i$Recorder Window$i$ saves a record of what you have done. This record is a script that describes all the steps necessary to draw your graph. To run the script in the $i$Recorder Window$i$ select $i$Run˚Recorder$i$. When you have finished making a graph, save the $i$Recorder Window$i$ script to a file. You can run this script when you want to recreate the graph in the future. To plot different data or to fine tune the appearance of your graph, you can edit the script in the Recorder Window. To draw the revised graph select Script>Run˚Recorder. To learn more about writing scripts, turn to Chapter 6. Selecting the $i$Recorder Window$i$: You can identify the $i$Recorder Window$i$ by looking for the microphone symbol in the $i$Window menu$i$. Use the $i$Recorder Menu$i$ to make a different window the $i$Recorder Window$i$ or to open a new recorder. See the description of the $i$Recorder Menu$i$ for more information. $$Data Window Asymptote Windows The $i$Data Window$i$ is the window Asymptote uses when reading data. The current $i$Data Window$i$, if one is open, is identified on the $i$Windows Menu$i$ by a symbol with numbers 1,2,3 on it. To make a different window the $i$Data Window$i$, select its name from the $i$Data Menu$i$. You can also use the $i$Data$i$ menu to open a new Text Editor Window as the $i$Data Window$i$. SEE ALSO: $i$Reading Data$i$ $b$datafile$b$ $$Graph Window Asymptote Windows The $i$Graph Window$i$ is where Asymptote creates your graph. To zoom the graph to show more detail, move the mouse to the $i$Graph Window$i$, hold down the command key and click on the portion of the graph that you want to see in more detail. To zoom out, hold down the command and options keys together and click anywhere in the $i$Graph Window$i$. To print your graph select $i$Print Graph$i$ from the $i$File$i$ menu or type $b$print$b$ in the $i$Command Window$i$. $$Status Window Asymptote Windows The $i$Status Window$i$ keeps you informed about what Asymptote is doing, and provides valuable information about the state of your session with Asymptote. Use the $i$Status Window$i$ to check on the value of a variable in the $i$graphics environment$i$, to see which data file is open, or to check the value of a user variable. The $i$Status Window$i$ is particularly valuable when you are debugging a script (see Chapter 6). While you are executing a script in Asymptote, the title of the $i$Status Window$i$ changes to let you know the line number and the name of the script that is running. The items in the $i$Status Window$i$ are separated into groups. Most of these items are either variables in the $i$graphics environment$i$ or Asymptote variables. Variable names appear in the column on the right. SEE ALSO: $i$Variables & Constants$i$ $i$graphics environment$i$ $$Vectors Window Asymptote Windows Use the $i$Vectors Window$i$ to quickly the view the status of Asymptote's vectors. Click on the black triangles at the top of each column to select which vectors you want to view. Click on the scroll bar at the side of the $i$Vectors Window$i$ to scroll through the all the elements of the vectors you are viewing. The $i$Preferences$i$ dialog box allows you to suspend updates of the $i$Vectors Window$i$ while your scripts are executing. This makes scripts run faster. When your script stops running or is paused Asymptote redraws the $i$Vectors Window$i$. $$Command Window Asymptote Windows Sometimes typing a command is faster than selecting menus and responding to dialog boxes. After you type a command in the $i$Command Window$i$ press Return or Enter. Asymptote executes the command and saves it to the current $i$Recorder Window$i$ (if one is open). To edit the command before you press Return, click the text with the mouse or press the left or right arrow keys. The up and down arrow keys have a special purpose in the $i$Command Window$i$. If you press the up arrow while the Command Window is active, Asymptote brings the current $i$Recorder Window$i$ to the front. Press the down arrow key while the $i$Recorder Window$i$ is active to bring the $i$Command Window$i$ to the front. Note that when you issue a command in the $i$Command Window$i$ using '?' for its arguments, Asymptote gets the values for the arguments from you interactively using dialog boxes or the graph cursor. It then records the command in the recorder window with the values 'filled-in'. This is a convenient way to enter a command if you don't remember what the arguments to the command are or if you don't remember their proper order. You can also use '?' to read coordinates from the graph. For example if you type: moveto ? in the $i$Command Window$i$, Asymptote activates the graph cursor, gets the new x,y position when you click the mouse, and then enters the $b$moveto$b$ command at the end of the recorder with the x,y coordinates filled in. If you clicked on (3.292,29.9) in graph coordinates, Asymptote enters the command: moveto 3.292 29.9 in your recorder. If you always want to be prompted for the x,y coordinates for the moveto command every time your script executes, then put moveto ? directly into your script (don't type it in the $i$Command Window$i$). Every time Asymptote encounters this command it activates the cursor and gets the new x,y position from you using the mouse. $$Variables Window Asymptote Windows The $i$Variables Window$i$ is a list of all the variables and their current values. The variable name appears in the left column, while the right column contains the current value of the variable. As you create new variables they appear at the bottom of the list. To change a user variable use the $b$set$b$ command. SEE ALSO: $i$graphics environment$i$ $i$Variables & Constants$i$ $$Vectors Window Asymptote Windows Use the $i$Vectors Window$i$ to examine the contents of Asymptoteàs vectors. Click the black triangles at the top of each column to pop-up a menu. Use the pop-up menu to select the vector you want to view in each column. For convenience you can select Show Stack from the pop-up menu to have Asymptote display the current contents of the calculator stack. Showing the stack in the $i$Vectors Window$i$ is very useful when you are debugging $b$rpn$b$ calculations. SEE ALSO: $b$rpn$b$ $i$Reading Data$i$ $$Calculator Window Asymptote Windows You can write expressions for Asymptoteàs vector calculator with the $i$Calculator Window$i$. Simply click the various buttons in the calculator and Asymptote calculates the result. It also stores the appropriate $b$rpn$b$ command in your Recorder, giving you a complete record of your calculation which you can play back later. If you are not familiar with reverse polish notation, see Appendix˚D of the $i$Users Guide$i$. SEE ALSO: $b$rpn$b$ $$Variables Window Asymptote Windows The $i$Variables Window$i$ is a list of all the variables with their current values. The variable name appears in the left column, while the right column contains the current value of the variable. As you create new user variables they appear at the bottom of the list. To change a user variable use the $b$set$b$ command. SEE ALSO: $i$Variables & Constants$i$ $b$set$b$ $$Movie Window Asymptote Windows The $i$Movie Window$i$ lets you view QuickTime movies. The controls at the bottom of the $i$Movie Window$i$ let you play a movie or step through its frames one at a time. See the description of the $i$Movie Menu$i$ for more information about playing movies SEE ALSO: $i$Movie Menu$i$ $b$moviefile$b$ $b$movieframe$b$ $$areaxy Calculate the area under the curve y = f(x) ARGUMENTS: none DESCRIPTION: Use $b$areaxy$b$ to calculate the integrated area under the curve $i$y$i$= f($i$x$i$) using the trapezoidal rule. Asymptote stores the result in the user variable $i$area$i$. If you want to have more accuracy in the area calculation, consider first using $b$spline$b$ to interpolate the curve with more ($i$x$i$, $i$y$i$) data points. Asymptote uses all the ($i$x$i$,$i$y$i$) data points to calculate the area. This means that points in the $i$x$i$ and $i$y$i$ arrays (including those outside your graph limits) will be used in the area calculation. If you don't want to include some of the ($i$x$i$,$i$y$i$) points in the area calculation, set their $i$y$i$ values to zero using the $b$rpn$b$ command as in the example below SEE ALSO: $b$spline$b$ EXAMPLES: readcol y 3 readcol x 2 areaxy % find the area under to curve and store in $i$area$i$ drawlabel left Area = \area % print the result on the graph % Find the area for X between 10 and 100: rpn <x 10 > <x 100 < + <y * >y % set y to zero if X < 10 or X > 100 areaxy % calculate the area drawtitle Area for points with 10 < X < 100 = \area $$ask variableName trueText falseText query Ask the user for a true or false response and store the result in a user variable ARGUMENTS: variableName ± the name of a user variable to set trueText ± text for the true (result = 1) button falseText ± text for the false (result = 0) button query ± the question to ask DESCRIPTION: Use $b$ask$b$ to display a dialog box that asks a yes/no (true/false) question. Asymptote stores the response to the question in a user variable. You might use $b$ask$b$ to control the execution of a script by asking a plain English question such as ¼Do you want to plot another data file½ or ¼Plot the best fit model on top of the data?½. You can also use the $b$ask$b$ to have Asymptote display a dialog box that has only a single button response. You might use such a dialog box to alert the user to some condition or provide them with some information while a script is running. To hide one of the buttons, specify " " for its name. If you hide one of the buttons, the other button is made the default response. You can't hide both buttons. Here's and example of using the $b$ask$ command to display a one button dialog that lets the user know what to do when the graph cursor is activated with the 'moveto ?' command that follows. ask OK " " Please click on the point with the graph cursor. moveto ? SEE ALSO: $b$set$b$ $b$if$b$ $b$repeat$b$ $b$while$b$ EXAMPLES: set continue true % set the default response to ¾trueà (1) ask continue Yes No Do you want to continue? if continue false = then stop set PlotOnTop true ask PlotOnTop "On Top" "Erase first" Plot the next curve on top of the last? if PlotOnTop false = then clear else plotline set DoQuit false ask DoQuit "Yes, exit to finder" "No, don't quit" Would you like to quit? if DoQuit then quit ask Normalize "Normalize Y" No Normalize the y data to its maximum? if Normalize then rpn <y max / >y $$backcolor r g b OR colorName Set the background color of the $i$Graph Window$i$ ARGUMENTS: r, g, b ± red green blue color values in percent (0 to 100) or colorName ± the name of a color (red, green, blue, magenta, yellow, purple, black, white) DESCRIPTION: Use $b$backcolor$b$ to change the background color of the $i$Graph Window$i$. The $b$backcolor$b$ command is especially useful when you are taking pictures of the screen or when you are making a presentation. You can use$b$backcolor$b$ to choose the background color and then $b$fullscreen$b$to expand the $i$Graph Window$i$ to fill the screen. To choose a color interactively type backcolor ? in the $i$Command Window$i$. SEE ALSO: $b$fullscreen$b$ EXAMPLES: backcolor 80 80 80 % set the background color to light gray pencolor black drawframe % draw a black frame on the gray background backcolor black % set the background color to back pencolor white % set the pen color to white myscript % run my script and draw a white graph on black fullscreen on % expand the graph to fill the screen backcolor 10 90 25 % set the background to a particular color backcolor ? % Choose a color using a color wheel. Put this command % in a script to open the color wheel each time you run % the script. % Type this command in the $i$Command Window$i$, select the % color from a color wheel and Asymptote records the % appropriate backcolor command for you in the Recorder. $$binxy nbins [ operation [ xstart xend ] ] Bin the x, y data into equally spaced bins ARGUMENTS: nbins ± number of bins to calculate operation ± the operation to perform for each bin: count (=0) => count the number of points in each bin average(=1) => average the $i$y$i$ values that fall in each bin sum (=2) => sum the $i$y$i$ values that fall in each bin xstart ± x value for the start of the first bin xend ± x value for the end of the last bin DESCRIPTION: Use $b$binxy$b$ to calculate the histogram of the $i$y$i$ data values. Although $b$binxy$b$ accepts up to four arguments, you must supply on the first argument (nbins), the number of bins to calculate. The second argument, is the operation to perform on each bin (operation), and the third and fourth arguments are the smallest and largest $i$x$i$ values you want binned (xstart, xend). If you don't specify the operation, Asymptote simply counts the number of points that fall into each bin (for example a frequency distribution). If you donàt specify xstart and xend, $b$binxy$b$ uses the current graph limits (xleft and xright) for xstart and xend (see $b$graphlimits$b$). When $b$binxy$b$ executes, it goes through the ($i$x$i$, $i$y$i$) data points one by one. First it uses the $i$x$i$ value of the point to determine what bin needs to be modified. Then, $b$binxy$b$ uses the $i$y$i$ value of the point to update the value in the bin. What Asymptote calculates depends on the operation you specify. If the operation is 'count' (=0) Asymptote simply counts the number of points that fall into each bin. For 'average' (=1) and 'sum' (=2) Asymptote calculates the average or sum of the points that fall in each bin. After all the ($i$x$i$,$i$y$i$) points have been processed, Asymptote replaces the $i$x$i$ values with the $i$x$i$ values of the bin centers, stores the bin values in the $i$y$i$ vector and sets the number of points to the number of bins. Although you can use any plot command to plot the bin values, $b$plothistogram$b$ produces a skyline-like plot that reflects the fact that the data have been binned. Remember that $b$binxy$b$ uses both the $i$x$i$ and $i$y$i$ values when you specify ¾averageà and ¾sum.à If you want to calculate a sum or average histogram for the $i$x$i$ values only, use $b$rpn$b$ to copy the $i$x$i$ vector into the $i$y$i$ vector before you use $b$binxy$b$ to calculate the histogram (see the example below). SEE ALSO: $b$plothistogram$b$ $b$graphlimits$b$ EXAMPLES: readcol x 4 readcol y 5 graphlimits % Set the limits to show all points binxy 100 sum % Sum the y values of the points in to 100 bins in x graphlimits % Set the limits to show all bins plothistogram % plot the bins as a histogram binxy 50 count 10.2 12.3 % Count the number of x values that fall into % 50 bins ranging from 10.2 to 12.3 in x binxy ? % Ask for the bin parameters interactively $$clear Clear the graph and release the memory it occupies ARGUMENTS: none DESCRIPTION: When you select $b$clear$b$, Asymptote erases the $i$Graph Window$i$ and frees the memory used by the graph. If you like, you can use File>Options>Preferences to have Asymptote erase the graph automatically whenever you run the script in the $i$Recorder Window$i$. SEE ALSO: $i$Preferences$i$ $$cliptoframe [ value ] Choose whether to clip drawing to the graph frame or not ARGUMENTS: value ± if $i$true$i$ then clip drawing to the graph frame else allow drawing outside the frame DESCRIPTION: Use $b$cliptoframe$b$ to control whether Asymptote clips (truncates) all drawing to the interior of the graph frame. Set $b$cliptoframe$b$ to false if you want lines, labels and points to extend outside the graph frame. If you donàt specify the single argument to $b$cliptoframe$b$, Asymptote sets $b$cliptoframe$b$ to true. Most of the time you will want to have $b$cliptoframe$b$ set to true. If you want to annotate your graph with labels or arrows that extend outside the frame, set $b$cliptoframe$b$ to false then draw your annotations (see the example below). SEE ALSO: $i$Preferences$i$ EXAMPLES: cliptoframe false % donàt clip all subsequent drawing to the frame cliptoframe % set clip to frame to true plotline % plot a line which is clipped to the frame limits moveto xright 10 + ytop 10 + % move to a position just outside the frame cliptoframe false % make it possible to draw outside the frame drawlabel centerright This is an interesting point! moveto xright 10 + ytop 10 + % move the pen in front of the label drawarrowto x(10) y(10) % draw an arrow pointing to the 10th point $$closewindow [ windowname ] Close a window and release the memory it occupies ARGUMENTS: windowname ± the name of the window to close DESCRIPTION: Use $b$closewindow$b$ in a script to close a window when it is no longer needed. If you donàt supply the name of the window to close, Asymptote closes the currently running script. Closing windows frees up memory and reduces screen clutter. With $b$closewindow$b$, your scripts can close windows automatically when they are no longer needed. For example, you might write a script that opens a large file in the $i$Data Window$i$, reads values from the file into the $i$x$i$ and $i$y$i$ vectors, then closes the $i$Data Window$i$ to free up the memory it occupies. You can also put $b$closewindow$b$ at the end of a script to close it automatically after it finishes running. This is particularly useful at the end of the ¾Asymptote Startup Scriptà or in any script that performs a task and is no longer needed. ¥ Note: If you want to hide a window on screen but keep its contents loaded in memory, use $b$hidewindow$b$ rather than $b$closewindow$b$. A hidden window still appears in the Windows menu where you can select its name and make it visible again. See $b$hidewindow$b$ for more details. SEE ALSO: $i$Startup Script$i$ $b$hidewindow$b$ $b$showwindow$b$ EXAMPLES: close March1988 data % close the window "March 1988 data" close \f % close the current data file close % close this window $$cursor Activate the graph cursor and read values from the graph ARGUMENTS: none DESCRIPTION: Use $b$cursor$b$ to activate the $i$Graph Window$i$ cursor and read information from your graph. Asymptote activates the $i$Graph Window$i$ and draws cross-hairs attached to the cursor. As you move the mouse Asymptote displays the current cursor position and the difference between that position and the current position of the pen. Click the mouse to make the cursor disappear. Note that $b$cursor$b$ does not move the pen. Use the $b$moveto$b$ command if you want to use the graph cursor to move the pen. SEE ALSO: $b$moveto$b$ $$datacolumns [ startcolumn [ endcolumn ] ] Specify what columns or characters to read from the data file ARGUMENTS: startcolumn ± first column or character to read from each line endcolumn ± last column or character to read from each line DESCRIPTION: To specify the which columns you want to read from your data file, use the $b$datacolumns$b$ command. After you specify which columns of your data file you want to read, use $b$readcolumn$b$ or $b$readrow$b$ to actually read the data into Asymptoteàs vectors. To read data from all columns of your data file, execute $b$datacolumns$b$ with no arguments. If you specify the first argument, startcolumn, Asymptote reads from that column to the last column in each row of your data file. To specify both the starting and ending columns to read, supply both arguments to the $b$datacolumns$b$ command. The two ways to use $b$datacolumns$b$ are described below: READING FROM ROWS : When you are using $b$readrow$b$ to read your data, the $b$datacolumns$b$ command tells Asymptote which columns of the data file to read. Asymptote looks for any number of white space characters (spaces or tabs) to identify separate columns in your data file. For example, if row 10 of the data file looked like this: 123.2 12E34 23 45.6 34 99.202 -20.083 "a label" And you wanted to read the values 23 45.6 34 from the 3rd, 4th and 5th columns into the $i$y$i$ vector, you would issue these commands: datacolumns 3 5 % select columns 3 through 5 inclusive readrow y 10 % read the three values from row 10 and store them in y READING FROM COLUMNS: When used in conjunction with the $b$readcolumn$b$ command, the $b$datacolumns$b$ command tells Asymptote which $i$characters$i$ of each line to use when reading data. Normally the columns of your data file will be separated by spaces or tabs and it will not be necessary to use $b$datacolumns$b$ when reading from columns of a file. If the values in your data file are run together without spaces or tabs to separate them, use $b$datacolumns$b$ to identify which characters of each line you want to read. For example, if a portion of your data file looked like this: FREQ=12.25E+13 TEMP=125 RIN=98 514.2 FREQ=12.29E+13 TEMP=116 RIN=89 746.4 FREQ=12.33E+13 TEMP=137 RIN=56 982.2 And you wanted to read the values 125 116 and 137 which appear in characters 20 through 22 of each line, issue the commands: datacolumns 20 22 % tell Asymptote to ignore all but characters % 20 through 12 of each line readcolumn y 1 % read the first value (starting at character 10) % into the e vector Notice that this example uses 1 for the column number for the $b$readcolumn$b$ command. This is because when you use $b$datacolumns$b$ to specify which $i$characters$i$ to use in each line, Asymptote $i$ignores all the other characters in the line$i$. Asymptote sees each line as beginning and ending with the characters you specify in the $b$datacolumns$b$ command. Therefore, you can use the $b$datacolumns$b$ command to mask out all but the characters you want to read. Note: To help you count characters in a line, use Edit>Configure to select a monospaced font (for example, Courier or Monaco) rather than a proportionally spaced font for your data file. When you use a mono-spaced font, the characters in each line are the same width making them easier to count. SEE ALSO: $b$datalines$b$ $b$datafile$b$ $b$readcolumn$b$ $b$readrow$b$ EXAMPLES: datacolumns 3 20 % use columns 3 through 20 readrow x 10 % read the values in columns 3 though 20 of line 10 % into the x vector. datalines 1 13 % read from lines 1 through 13 datacolumns 10 34 % ignore all but characters 10 through 34 of each line readcolumn x 2 % read the 2nd item starting with character 10 of each line % and store in x datacolumns 4 % Skip the first 3 columns and read to the end of each line datacolumns % use all columns (or characters) when reading data. % same as ¼datacolumns 0 0½ $$datafile filename Open a data file with the name you specify ARGUMENTS: filename ± the name of the data file DESCRIPTION: Use $b$datafile$b$ to specify the data file Asymptote should use when it reads data with the $b$readrow$b$ and $b$readcolumn$b$ commands. If the data file you specify isnàt already open in a Text Editor Window, Asymptote searches for it automatically using the $i$Search paths$i$ file. DATA FILE FORMATS: Asymptote reads data from unformatted (ASCII) text files. You can read numbers or labels from either rows or columns of the file. Data files are easiest to read if the items in each line are separated by white space characters (any number of spaces or tabs) or a single comma. You can also skip over lines or columns in your data file and you can read data from files that donàt have the items on a line separated from one another. For a complete description of how to read data, see $i$Reading Data$i$ in Chapter 3 or type help Reading data in the $i$Command Window$i$. USING THE SEARCH PATHS FILE TO OPEN YOUR DATA FILE AUTOMATICALLY: If you have difficulty getting Asymptote to locate a file for you automatically, make sure youàve properly specified a search path to the file in your Search Paths file. Also, check to make sure you have spelled the name of the file correctly (including spaces). For help specifying search paths, see $i$Search Paths$i$ or type help Search Paths in the $i$Command Window$i$. SPECIFYING THE FULL OR PARTIAL PATH NAME OF YOUR DATA FILE: It is best to let Asymptote locate files for you automatically by including the path to your file in the Search Paths file. Locating files this way has the advantage that if you move your files to a different location, you need only change your Search Paths file to have Asymptote locate them automatically. It is possible, however, to specify the location of a file completely when you issue the $b$datafile$b$ command. The complete description of a fileàs location is called the ¼full path name.½ Full path names start with a disk name (usually your hard disk name) followed by the name of each subfolder (separated by colons) and the filename. For example, to locate the file "xyz" in the folder "March 12" which is on the hard disk named "My Disk" use datafile My disk:March 12:xyz Itàs also possible to give a ¼partial path name½ if the file you want is in the Asymptote folder or in some folder within the Asymptote directory. For example, if the folder "March 12" were in the same folder with Asymptote, you could use the partial path name: datafile :March 12:xyz Notice that partial path names begin with a colon, while full path names do not. Partial path names always start their search with the same folder as Asymptote. OPENING A SEQUENCE OF FILES BY NUMBER: If you have a sequence of data files to plot, you can plot them automatically by including a user variable in the filename. For example, suppose you have a series of files named, ¼Run 1 Raw Data½, ¼Run 2 Raw Data½, ¼Run 3 Raw Data½. First, create a script called ¼plotraw½ that looks like this: clear % clear the $i$Graph Window$i$ datafile Run \i Raw Data readcolumn x 1 readcolumn y 2 % create the plot with more commands here... print % print the graph Notice that the $b$datafile$b$ command in this script inserts the user variable $i$i$i$ into the filename. Next, create a short script that increments $i$i$i$ while running the ¼plotraw½ script: for i from 1 to 3 do plotraw When you insert a user variable in a filename, precede the name with a \ (backslash) and follow it with a single space. Asymptote removes the backslash and the space and substitutes the variable. Asymptote uses the settings of $b$notation$b$ and $b$digits$b$ to convert the numerical value of the variable to text. SEE ALSO: $i$Reading data$i$ $i$Search Paths$i$ $i$Window menu$i$ $b$datalines$b$ $b$datacolumns$b$ $b$readcolumn$b$ $b$readrow$b$ EXAMPLES: datafile june data % open the file "june data" datafile :march 1988:run1 % open "run1" in the folder "march 1988" datafile ? % open a file interactively via a dialog box set counter 3 datafile test #\counter data % open the data file ¾test #3 dataà datafile test\counter -new % open the data file ¾test3-newà $$datalines [ startline [ endline ] ] Specify what lines of the data file to use when reading data ARGUMENTS: startline ± staring line number to use when reading data endline ± last line (inclusive) to use when reading data DESCRIPTION: Use the $b$datalines$b$ command to tell Asymptote which lines of the data file you want to use when reading data. You can use $b$datalines$b$ to skip over header lines at the beginning of your data file or to read a particular set of lines rather than all of the lines in a file. To read every line from the data file, issue $b$datalines$b$ with no arguments. To skip over lines at the beginning of your data file (a header for example), specify only the first argument, $i$startline$i$, when you issue the $b$datalines$b$ command. Specify both startline and endline if you want to read specific lines from your data file. ¥ Note If you don't want to count lines in the data file, select the lines you want to read and type datalines ? in the $i$Command Window$i$ or select $i$Lines$i$ from the $i$Data menu$i$. Asymptote prompts you with the $b$datalines$b$ dialog box, and enters the lines you selected as the default starting and ending lines. Another way to determine the line number of a particular line is to click that line and select Edit>Go˚To˚Line Asymptote displays the line number you clicked as the default choice in the ¼Go To Line½ dialog box. SEE ALSO: $b$datafile$b$ $b$datacolumns$b$ $b$readcolumn$b$ $b$readrow$b$ $i$Go to Line #...$i$ EXAMPLES: datalines 10 23 % use lines 10 through 23 when reading data datalines % use all lines in the data file % same as ¼datalines 0 0½ datalines ? % to choose the data lines interactively $$digits [ n ] Set the number of digits to display when converting numbers to labels ARGUMENTS: n ± number of digits to display when converting numbers to labels DESCRIPTION: Use $b$digits$b$ to specify how many significant digits you want Asymptote to display when it converts numbers into labels. To decide how to convert numbers into text, Asymptote uses the number of digits you specify and the $b$notation$b$ you have chosen. For most notation formats, $b$digits$b$ selects the number of significant digits you want to display in the number. Use $b$digits$b$ = 0 to show all the digits in a number. For the 'decimal' notation ($b$notation$b$ = -2), $b$digits$b$ specifies how many digits to show $i$after$i$ the decimal point. With 'decimal' notation set $b$digits$b$ to a large number (say >10) if you want Asymptote to show all the digits in the number. The following examples show how Asymptote converts the value 123.456789 to a label using a variety of notation formats. $b$notation$b$ $b$digits$b$ Label decimal 4 123.4568 2 123.46 0 123 For the ¾decimalà notation, $b$digits$b$ is the number of digits to display after the decimal point. If the value is 0, the ¾decimalà notation displays ¼0.0½ unless $b$digits$b$ is 0, in which case a ¼0½ with no decimal point is displayed. $b$notation$b$ $b$digits$b$ Label float 4 123.5 2 123 0 123.456789 For the ¾floatà notation, $b$digits$b$ is the number of significant digits to display. The float notation always displays ¼0½ if the value is 0. $b$notation$b$ $b$digits$b$ Label general 4 123.5 2 123 0 123.456789 The ¾generalà format uses ¾scientificà notation if the value is greater than 1˚x10^6, otherwise the ¾floatà notation is used. The general notation always displays ¼0½ if the value is 0. The ¾defaultà notation always uses scientific notation: $b$notation$b$ $b$digits$b$ Label default 4 1.235˚x˚10^2 2 1.2˚x˚10^2 0 1.23456789˚x˚10^2 For the ¾defaultà notation, $b$digits$b$ is the number of significant digits in the mantissa. The default notation always displays ¼0½ if the value is 0. The ¾scientificà notation uses scientific notation: $b$notation$b$ $b$digits$b$ Label scientific 4 1.235˚x˚10^2 2 1.2˚x˚10^2 0 1.23456789˚x˚10^2 For the ¾scientificà notation, $b$digits$b$ is the number of significant digits in the mantissa. If the value is 0 and $b$digits$b$is 0, ¾scientificà notation displays ¼0½, otherwise ¼0.0½ is displayed. The ¾hhmmssà notation displays hour, minutes and seconds: $b$notation$b$ $b$digits$b$ Label hhmmss 4 123h 27m 24.4s 2 123h 27m 0 123h 27m 24s For the ¾hhmmssà notation, if $b$digits$b$ is 0, the time is displayed with no decimal point in the seconds portion. If $b$digits$b$ is 1, only the hours are displayed. If $b$digits$b$ is 2, the hours and minutes are displayed. If $b$digits$b$ is >3, $b$digits$b$ - 3 is the number digits to display after the decimal point in the seconds portion of the label. If the value is 0, ¼0h½ is always displayed. The ¾ddmmssà notation displays degrees, minutes and seconds: $b$notation$b$ $b$digits$b$ Label ddmmss 4 123¡27à 24.4àà 2 123¡ 27à 0 123¡ 27à 24àà For the ¾ddmmss notation, if $b$digits$b$ is 0, the angle is displayed with no decimal points in the seconds portion. If $b$digits$b$ is 1, only the degrees are displayed. If $b$digits$b$ is 2, the degrees and minutes are displayed. If $b$digits$b$ is >3, $b$digits$b$ - 3 is the number digits to display after the decimal point in the seconds portion of the label. If the value is 0, ¼0¡½ is always displayed. SEE ALSO: $b$notation$b$ $b$drawlabel$b$ $b$drawtitle$b$ $b$drawxlabel$b$ $b$drawylabel$b$ $b$drawlabel$b$ EXAMPLES: digits ?How many digits should I show in the label? set temp 1.23456789 moveto ? notation general drawlabel temp = \temp digits 2 set temp y(10) % use a variable to hold the value of the 10th y point drawlabel belowleft Y value of point #10 = \temp $$drawarrowto x y Draw an arrow from the current pen position to (x, y) ARGUMENTS: x ± x position at the end of the arrow y ± y position at the end of the arrow DESCRIPTION: Use $b$drawarrowto$b$ to draw a line from the current pen location to the coordinates you specify. Asymptote caps the line with an arrowhead. Asymptote uses the current pen properties when you draw arrows. Use any of the commands like $b$pensize$b$ and $b$pendash$b$ to change the appearance of the line (see $i$graphics˚environment$i$). You can change the size of the arrowhead with the $b$scale$b$ command. A convenient way to add a arrow to your graph is to use a question mark following the $b$drawarrowto$b$ command. Type drawarrowto ? in the $i$Command Window$i$ or in a script. Asymptote activates the graph cursor. When you click, Asymptote draws an arrow that points to the location you clicked. Remember, to draw arrows that extend outside the graph frame, set $b$cliptoframe$b$ to false before you use $b$drawarrow$b$. otherwise, Asymptote truncates your line if it extends outside the frame. SEE ALSO: $i$graphics environment$i$ $b$moveto$b$ $b$drawto$b$ $b$cursor$b$ $b$pensize$b$ $b$pendash$b$ $b$penpattern$b$ $b$pencolor$b$ $b$scale$b$ $b$cliptoframe$b$ EXAMPLES: drawarrowto 3.4 56.9 % draw arrow from current (x, y) to (3.4 56.9) drawarrowto ? % choose x, y using the cursor pencolor red pendash short drawarrow 4 y 10 + % draw a red, dashed arrow to (4,y+10) drawarrowto x(5) y(5) % draw a arrow to the 5th data point. $$drawaxis axis[tickpos[labelpos[drawline[drawticks[drawlabels]]]]] Draw an axis on one side of the graph frame ARGUMENTS: axis ± selects which axis to draw bottom (=1) left (=2) top (=3) right (=4) tickpos ± selects whether to draw the tick marks inside or outside the graph frame inside (=1) outside (=2) labelpos ± selects whether to draw the tick mark labels inside or outside the frame inside (=1) outside (=2) drawline ± selects whether to draw the axis line or not noline (=0) line (=1) drawticks ± selects whether ticks should point inside or outside the graph noticks (=0) inside (=1) outside (=2) drawlabels ± selects whether to draw tick labels parallel or perpendicular to the axis nolabels (=0) parallel (=1) perpendicular (=2) DESCRIPTION: Use $b$drawaxis$b$ to draw individual axes on your graph. Although the $b$drawframe$b$ command is a convenient way to draw axes on your graph, there are times youàll need to have more control drawing axes. That's when the $b$drawaxis$b$ command is useful. The first argument to $b$drawaxis$b$ specifies which axis to draw. Specify either the top, bottom, left or right axis of the frame. You must supply the first argument to $b$drawaxis$b$, all the other arguments are optional. The second argument lest you specify whether or not you want Asymptote to draw the axis line. This is useful if you are drawing an axis line in a different style or color that is different from the tick marks. Finally, the third and fourth arguments to $b$drawaxis$b$specify how tick marks and tick mark labels, if any, are drawn. Asymptote uses the variables of the $i$graphics environment$i$ to draw the axis. Before you issue the $b$drawaxis$b$ command, make sure you set the following variables: TO: USE: Set starting or ending values of the axis $b$graphlimits$b$ Set the major and minor tick mark spacing $b$graphticks$b$ Set the position the graph frame $b$graphframe$b$ Set the line size or color of the axis $b$pensize$b$, $b$pencolor$b$, etc. Set the size of tick marks and tick labels $b$scale$b$ Set the default size for tick marks $b$ticksize$b$ Set the default size for tick labels $b$fontsize$b$ Set the notation for tick labels $b$notation$b$ Set the font for tick labels $b$fontname$b$ Remember you can issue the $b$drawaxis$b$ command more than once to draw an axis. For example, you might call $b$drawaxis$b$ to draw thin tick marks then call $b$drawaxis$b$ again to draw a thicker axis line. You could accomplish this with the following commands: pensize 0.25 % set up for very thin tick marks % draw just the ticks and labels: drawaxis bottom inside outside noline inside parallel pensize 2 % set up for a thick axis line % draw just the axis line: drawaxis bottom inside outside line noticks nolabel To draw tick marks in a different color than the axis line, change the pen color between the two calls to drawaxis with $b$pencolor$b$. SEE ALSO: $i$graphics environment$i$ $b$graphticks$b$ $b$graphframe$b$ $b$graphlimits$b$ $b$notation$b$ $b$scale$b$ $b$fontname$b$ $b$ticksize$b$ $b$ticksize$b$ $b$pensize$b$ $b$pendash$b$ $b$pencolor$b$ EXAMPLES: % Draw a basic frame: pensize .25 % Draw thick lines fontname Times % Choose the Times font for tick labels graphlimits 1.2 34 0 0 % x axis goes from 1.2 to 34 but % choose y limits based on max, min of % the current y data graphticks % Let Asymptote choose tick spacing % Draw the axis on the bottom of the graph frame: drawaxis bottom inside outside line inside parallel % Draw a frame with thin tick marks and a thick border labels and tickmarks % outside the frame pensize 2 % Start out with thick lines % Draw a fat line along left side: drawaxis left outside outside drawline noticks nolabels pensize .25 % then change to thin lines and % Draw thin tick marks inside: drawaxis left outside outside noline inside drawlabels % Plot two sets of y data using different axes on the left and right sides of the graph: readcol x 1 % read x readcol y 2 % read the first set of y data graphlimits % auto limits % Draw all but the right axis using the defaults for drawframe: drawaxis bottom inside outside line inside perpendicular drawaxis top inside outside line inside nolabels drawaxis left inside outside line inside perpendicular pendash % solid line plotline % plot the first set of y data readcol y 3 % read the second set of y data graphlimits % find the max and min for these data % Draw the specially formatted right axis: drawaxis right inside outside line inside perpendicular pendash dot % set up for a dotted lines plotline % plot the second set of y data as a dotted line drawaxis ? % choose how to draw an axis graphically $$drawframe [ ticks [ labels [ draw [ bottom [ left [ right [ top ]]]]]]] Draw a frame around the graph with or without tick marks and tick mark labels ARGUMENTS: ticks ± selects whether ticks should be drawn inside or outside the frame inside (=1) outside (=2) labels ± selects whether tick mark labels should be drawn inside or outside the frame inside (=1) outside (=2) draw ± turns tick mark drawing on and off noticks (=0) ticks (=1) bottom ± selects whether to draw tick labels parallel or perpendicular to the frame left nolabels (=0) top parallel (=1) right perpendicular (=2) DESCRIPTION: Use $b$drawframe$b$ to quickly draw a frame around your graph and label the $i$x$i$ and $i$y$i$ axes with tick marks. If you need greater control over how the axes should look, or if you want to draw only one axis at a time, use the $b$drawaxis$b$ command instead. Before you use $b$drawframe$b$, make sure you set the variables of the graphics environment. TO: USE: Set starting or ending values of the axis $b$graphlimits$b$ Set the major and minor tick mark spacing $b$graphticks$b$ Set the position of the graph frame $b$graphframe$b$ Set the line size or color of the axis $b$pensize$b$, $b$pencolor$b$, etc. Set the size of tick marks and tick labels $b$scale$b$ Set the default size for tick marks $b$ticksize$b$ Set the default size for tick labels $b$fontsize$b$ Set the notation for tick labels $b$notation$b$ Set the font for tick labels $b$fontname$b$ To draw complicated frames, you can issue use $b$drawframe$b$ more than once. For example, to draw a graph with a thick frame, thin tick marks and tick mark labels in the Helvetica font on all but the top of the frame you could use the following commands: graphlim 1 23 -1 10 % x runs from 1 to 23, y from -1 to 10 pensize 3 % thick lines for the frame drawframe inside outside noticks nolabels nolabels nolabels nolabels pensize .25 % set up to draw thin tick lines fontname Helvetica drawframe inside outside ticks parallel perpendicular nolabels perpendicular SEE ALSO: $i$graphics environment$i$ $b$drawaxis$b$ $b$graphticks$b$ $b$graphframe$b$ $b$graphlimits$b$ $b$notation$b$ $b$scale$b$ $b$fontname$b$ $b$fontsize$b$ $b$ticksize$b$ $b$pensize$b$ $b$pendash$b$ $b$pencolor$b$ EXAMPLES: drawframe ? % Choose settings interactively drawframe % Draw a basic frame automatically % This is the same as the above: drawframe inside outside parallel perpendicular nolabels nolabels % Draw ticks and tick mark labels outside the frame with labels % going all the way around the frame: drawframe outside outside parallel parallel parallel parallel $$drawgrid [ drawminor ] Draw a grid of lines at the major and optionally the minor tick marks ARGUMENTS: drawminor ± controls which grid lines to draw false => draw lines only at the major tick marks true => draw lines at the minor tick marks as well DESCRIPTION: Use $b$drawgrid$b$ with no arguments to draw a dotted line grid at each major tick mark. To draw grid lines at the minor tick marks, supply the single argument, drawminor, to $b$drawgrid$b$. Use drawminor =˚false to draw lines at only the major tick marks, and drawminor = true to draw lines at both the major and minor tick marks. When you supply the argument to $b$drawgrid$b$ you also have greater control over how to draw the grid lines. For example, you can change the dash pattern for the grid lines with $b$pendash$b$ and use $b$drawgrid$b$ to draw the grid lines. SEE ALSO $i$graphics environment$i$ $b$graphticks$b$ $b$pendash$b$ EXAMPLES: pendash dot drawgrid true % draw dotted grid lines on major and minor ticks pendash solid drawgrid false % draw solid lines at the major tick marks pendash ?Choose a dash pattern for the grid: drawgrid true $$drawlabel position text Draw a label on the graph ARGUMENTS: position ± specifies the label position relative to the pen: aboveleft (=7) above (=8) aboveright (=9) centerleft (=4) center (=5) centerright (=6) belowleft (=1) below (=2) belowright (=3) ¥ Note: This arrangement is the same as the keys on key boards equipped with key pads. text ± the text of the label DESCRIPTION: Use $b$drawlabel$b$ to add labels to your graphs. The first argument to $b$drawlabel$b$ specifies how Asymptote should position the label relative to the current pen position. For convenience you can also use Asymptoteàs built-in constants to specify the position or specify the number (1 through 9) directly. Remember, you can use $b$fontname$b$, $b$pencolor$b$, $b$scale$b$ and $b$rotation$b$ to alter the appearance of a label and you can use $b$fontsize$b$ to change the default size for labels. You can also include special $i$control characters$i$ in the text of your label to: ± change font within a label ± turn italics on or off ± draw super and subscripted characters ± insert the value of a user variable ± insert the current date or time ± insert the name of the current data file or the name of the $i$Recorder Window$i$ The easiest way to see how these control characters work is to select Plot>Draw Label, or type: drawlabel ? in the $i$Command Window$i$. Asymptote displays a dialog box in which you can construct your label interactively. As you type, Asymptote shows you what the label looks like. You can make selections in the dialog box to insert control characters that change the appearance of the text. The control characters in a label must be preceded by either one or two backslash, \, characters. Use a single \ to format only the next character in the label. Use ¼\\½ to change the format for all subsequent characters. CONTROL CHARACTERS: \\x - set mode x for all subsequent characters \x - set mode x for the next char only \t - Change the font to Times \h - Change the font to Helvetica \s - Change to the Symbol font \c - Change to the Courier font \u - shift up for superscript \d - shift down for subscript \f - insert the name of the current data file \r - insert the name of the $i$Recorder Window$i$ \@ - insert the current time \# - insert the current date To insert the name of a variable or a constant in a label, type a backslash (\) followed by the name of the variable and a single space. Asymptote needs the space following the variable name so it can determine where the variable name ends and the rest of the label begins. Asymptote removes the backslash, the space and replaces the name of the variable with the value of the variable converted to text. You can specify the format for the conversion with $b$notation$b$ and $b$digits$b$. Remember that to draw a label outside the graph frame, you need to set $b$cliptoframe$b$ to false before you use $b$drawlabel$b$. SEE ALSO: $i$graphics environment$i$ $i$User Variables$i$ $i$Asymptote Variables$i$ $b$fontname$b$ $b$scale$b$ $b$rotation$b$ $b$pencolor$b$ $b$textmode$b$ $b$moveto$b$ $b$drawto$b$ $b$notation$b$ $b$digits$b$ $b$cliptoframe$b$ $b$fontsize$b$ EXAMPLES: moveto 10 12 % position the pen at (10,12) drawlabel center Frequency (Hz) % draws the label "Frequency (Hz)" % centered on the current pen position. moveto ?Click where would you like to place the label: drawlabel ? % Get the text of the label interactively % using the Draw Label dialog box % Draw the label y = e(x2 + y2) + sin(t) to the right of the pen: drawlabel centerright y = e\\u(x\u2 + y\u2)\\d + sin(\st) % Put a label with the date and the name of the current data file in the upper % left hand corner of the graph: moveto \xright \xleft - .1 * \xleft + \ytop \ybottom - .9 * \ybottom + drawlabel 6 Data from: \f Date: \# % Set a user variable and use it in a label set runnumber 3 % draw the label ¼Run #3 data½ to the right of the pen drawlabel centerright Run #\runnumber data $$drawpoint Draw a point at the pen position ARGUMENTS: none DESCRIPTION: Use $b$drawpoint$b$ to draw a point on your graph. Asymptote draws the point at the current pen position. You can specify the symbol to draw with $b$pointsymbol$b$. You will probably find $b$drawpoint$b$ most useful when you are adding legends to your graph or when you want to draw a single point on your graph. The size and rotation of the point are controlled by the $b$scale$b$ and $b$rotation$b$ commands. Set the default label size with the $b$fontsize$b$ command. The current pen characteristics and fill pattern are also used to draw the point (see $i$graphics environment$i$). Remember that to draw a point outside the graph frame, you need to set $b$cliptoframe$b$ to false before you use $b$drawpoint$b$. SEE ALSO: $i$graphics environment$i$ $b$pencolor$b$ $b$pensize$b$ $b$penpattern$b$ $b$penmode$b$ $b$fillpattern$b$ $b$scale$b$ $b$rotation$b$ $b$moveto$b$ $b$drawto$b$ $b$cliptoframe$b$ $b$fontsize$b$ EXAMPLES: moveto x .1 + y % shift the position of the pen by .1 units in x pointsymbol 4 filled % choose to draw a filled square drawpoint % draw a filled square at the shifted position moveto ? % Position the pen interactively pointsymbol ?What point symbol? % Choose a point symbol graphically drawpoint $$drawtitle text Add a title to the graph centered above the graph frame ARGUMENTS: text ± the text of the title DESCRIPTION: Use $b$drawtitle$b$ to draw a title on your graph. Asymptote centers the title above the graph frame. You can change the position of the frame on the page with $b$graphframe$b$. To put the title somewhere else on the page, use $b$moveto$b$ and $b$drawlabel$b$ instead. As with any label, you can change any of the variables of the $i$graphics˚environment$i$.such as $b$fontname$b$, $b$pencolor$b$, and $b$scale$b$to change the appearance of the title and you can change the default label size with $b$fontsize$b$. The title text can also include control characters to format individual characters or words or to insert the date, the name of the data file or the value of a variable. See the description of the $b$drawlabel$b$ command for an explanation how to use control characters in labels. Remember, you can interactively edit and view how your title looks by typing the command drawtitle ? in the $i$Command Window$i$, or by selecting Draw>Title. SEE ALSO: $i$graphics environment$i$ $b$drawlabel$b$ $b$fontname$b$ $b$scale$b$ $b$pencolor$b$ $b$textmode$b$ $b$fontsize$b$ $b$moveto$b$ $b$drawto$b$ EXAMPLES: drawtitle The effect of gamma rays on man-in-the-moon marigolds fontname Helvetica scale 2.0 drawtitle H\sa Line Intensities from data file:\f $$drawto x y Draw a line from the current pen position to ($i$x$i$, $i$y$i$) ARGUMENTS: x, y ± $i$x$i$ and $i$y$i$ coordinates of the end of the line DESCRIPTION: Use $b$drawto$b$ to draw a line from the current pen location to the coordinates you specify. Asymptote uses the current pen properties to draw the line. Use any of the commands like $b$pensize$b$ and $b$pendash$b$ to change the appearance of the line (see $i$graphics environment$i$). A convenient way to draw a line on your graph is to use ? following the $b$drawto$b$ command. Type drawto ? in the $i$Command Window$i$ or in a script. Asymptote activates the graph cursor which you can use to position the end of the line with the mouse. You can also select Draw>Move˚To to activate the graph cursor. Remember that to draw a line outside the graph frame, you need to set $b$cliptoframe$b$ to false before you use $b$drawto$b$. SEE ALSO: $i$graphics environment$i$ $b$moveto$b$ $b$drawarrowto$b$ $b$cursor$b$ $b$pensize$b$ $b$pendash$b$ $b$penpattern$b$ $b$pencolor$b$ $b$scale$b$ $b$cliptoframe$b$ EXAMPLES: drawto 3.4 56.9 % draw a line from the current pen position to (3.4 56.9) drawto ? % set the end point of the line with the graph cursor pencolor red pendash short drawto 4 y 10 + % draw a red, dashed line from (x,y) to (4,y+10) pensize 4 % get ready to draw a fat line moveto 1 1 % move to (1,1) drawto x(10) y(10) % draw a line from (1,1) to the position % of the 10th data point $$drawxlabel text Add a label to the x axis of the graph ARGUMENTS: text ± the text of the label DESCRIPTION: Use $b$drawxlabel$b$ to label the $i$x$i$ axis of your graph. Asymptote draws $i$x$i$ labels centered below the graph frame. You can change the position of the frame on the page with the $b$graphframe$b$ command. If you want to put the $i$x$i$ label elsewhere on the page, use $b$moveto$b$ and $b$drawlabel$b$ instead. As with any label, you can change the appearance of the text by adjusting the variables of the $i$graphics environment$i$. You can include control characters in the label to format the text or to insert the value of a variable or constant. See the description of the $b$drawlabel$b$ command for an explanation. If you want to choose text of the label interactively, put the command drawxlabel ? into your script or select Draw>X˚Label. SEE ALSO: $i$graphics environment$i$ $b$drawlabel$b$ $b$drawylabel$b$ $b$drawtitle$b$ $b$fontname$b$ $b$scale$b$ $b$pencolor$b$ $b$textmode$b$ $b$fontsize$b$ $b$scale$b$ $b$moveto$b$ $b$drawto$b$ EXAMPLES: drawxlabel Frequency (Hz) pencolor gray drawxlabel Sin(\\st + o\\t) $$drawylabel text Add a label to the y axis of the graph ARGUMENTS: text ± the text of the label DESCRIPTION: Use $b$drawylabel$b$ to label the $i$y$i$ axis of your graph. Asymptote draws $i$y$i$ labels centered below the graph frame. You can change the position of the frame on the page with the $b$graphframe$b$ command. If you want to put the $i$y$i$ label elsewhere on the page, use $b$moveto$b$ and $b$drawlabel$b$ instead. As with any label, you can change the appearance of the text by adjusting the variables of the $i$graphics environment$i$. You can include control characters in the label to format the text or to insert the value of a variable or constant. See the description of the $b$drawlabel$b$ command for an explanation. If you want to choose text of the label interactively, put the command drawylabel ? into your script or select Draw>Y˚Label. SEE ALSO: $i$graphics environment$i$ $b$drawlabel$b$ $b$drawxlabel$b$ $b$drawtitle$b$ $b$fontname$b$ $b$scale$b$ $b$pencolor$b$ $b$textmode$b$ $b$fontsize$b$ $b$scale$b$ $b$moveto$b$ $b$drawto$b$ EXAMPLES: drawylabel Temperature (K) pencolor gray drawylabel Sin(\\st + o\\t) $$export [x][y][e][p][l] Write the values of Asymptoteàs vectors in the Data Window ARGUMENTS: x,y,e,p,l ± the names of the vectors to export (can be in any order) DESCRIPTION: You can use the export command to write out the values of Asymptote's vectors in the $i$Data Window$i$. First, use the datafile command to open a data file. Next, issue the $b$export$b$ command. You can follow the $b$export$b$ command with the name or names of the vectors you want to export. For example, to export the $i$x$i$ $i$y$i$ and $i$e$i$ vectors to the $i$Data Window$i$, use export x y e You can export vectors in any order. If you don't specify which vectors you want to export, Asymptote exports the $i$x$i$ and $i$y$i$ vectors. Asymptote uses the current value of the Asymptote variable $i$digits$i$ (set with the $b$digits$b$ command) to determine how many digits will follow the decimal point in floating point numbers. Large or very small numbers appear in exponential notation. You might also use export to save the results of some lengthy calculation in Asymptote. Remember, you can use the registers of the rpn calculator to store whole vectors. The $b$export$b$ command might also be useful when you use $b$readcursor$b$ to read data from your graph and export the data to another application. SEE ALSO: $b$datafile$b$ $b$digits$b$ $b$readcursor$b$ EXAMPLES: digits 3 % Use 3 digits following the decimal point export % Export the x and y vectors only export y e p % Export y e and p in that order export x y e p l % Export everything $$fillpattern pattern Set the fill pattern for points and polygons ARGUMENTS: pattern ± the number of the new pattern: 0 through 38 or the pattern name none, black, darkgray, gray, lightgray, squares, vertical, horizontal, diagonal, white, bricks DESCRIPTION: Use $b$fillpattern$b$ to set the fill pattern for drawing points and polygons. Valid pattern numbers are 0 through 38 or the names: none, black, darkgray, gray, lightgray, squares, vertical, horizontal, diagonal, white, bricks. These pattern numbers are Asymptote constants (see $i$Variables and Constants$i$). Remember, you can select Set>Fill˚Pattern or type fillpattern ? in the $i$Command Window$i$ to choose the fill pattern from a picture of the various fill patterns. SEE ALSO: $i$Variables and Constants$i$ $b$penpattern$b$ $b$pencolor$b$ $b$plotpoints$b$ $b$plotpolygon$b$ $b$plothistogram$b$ EXAMPLES: fillpattern gray % draw solid gray filled squares at each point pointsymbol 4 filled plotpoints fillpattern penpattern % make the fill pattern the same as the pen pattern rpn ran >x ran >y graphlimits fillpattern ?Pick a fill pattern for this polygon: plotpoly $$fitxy [[ N ] expression ] Fit y = f(x) with a polynomial or a function you specify N ± the order of the polynomial to fit (default = 1) 1 = linear, 2 = quadratic, 3 = cubic, etc,.. OR N ± the number of parameters in the function to fit expression ± an expression for the function to fit DESCRIPTION: Use $b$fitxy$b$ to fit a function to the ($i$x$i$, $i$y$i$) data points using least squares. The function can either be a polynomial or a general expression that you specify. ____________________ TO FIT A POLYNOMIAL ___________________________________ To fit a polynomial y = a0 + a1 x + a2 x^2 + ... + aN x^N to your ($i$x$i$, $i$y$i$) data, follow the $b$fitxy$b$ command with a single argument, N (the order of the polynomial to fit). For example, the command fitxy 3 fits the function y = a0 + a1 x + a2 x^2 + a3 x^3. You can use the values in the e vector to give a different weight to each of the ($i$x$i$, $i$y$i$) points in the polynomial fit. See Using Errors below. After the fit, Asymptote updates the values of the $i$a0$i$, $i$a1$i$, $i$a2$i$, ... , $i$aN$i$ user variables with the polynomial coefficients. It also stores the error for each coefficient (the diagonal elements of the covariance matrix) in the user variables $i$a0sig$i$, $i$a1sig$i$, ... , $i$aNsig$i$. Asymptote stores the chi square of the fit in the user variable chisq. You can use rpn and plotline to calculate the fit and plot it on top of your data. For example, to fit a 2nd order polynomial and plot the final fit use the following commands: fitxy 2 rpn <x 2 y^x a2 * <x a1 * + a0 + >y plotline When you select Data>Fit˚Y˚=˚F(x), Asymptote displays a dialog box which makes it easy to fit your data and plot the final fit. ____________________ TO FIT A FUNCTION ___________________________________ To fit an arbitrary function to your data, follow the $b$fitxy$b$ command with two arguments. The first argument is the number of parameters in the function you want to fit. The second argument is an rpn expression for the function. The expression should evaluate to a single argument. For example, to fit a sine wave with phase $i$a0$i$ and amplitude $i$a1$i$, you could use fitxy 2 x a0 - sin a1 * The expression "x a0 - sin a1 *" subtracts $i$a0$i$ from each x data point, calculates the sine and multiplies the result by $i$a1$i$. The easiest way to write $b$fitxy$b$ expressions is to select Data Fit Y = F(x) and use the fitxy dialog box to specify what you want to fit. Asymptote's curve fit dialog helps guide you through the process of fitting your data. INITIAL VALUES FOR PARAMETERS: Asymptote uses the Levenburg-Marquardt method to estimate the values of up to 32 free parameters by minimizing chi square. Asymptote must begin this process starting with your best guesses for the values of the model parameters. If you don't supply good initial values for the parameters, $b$fitxy$b$ will probably produce poor results. You can create and set the initial values of the fitting variables $i$a0$i$, $i$a1$i$, ... , $i$aN$i$ using the set command. If a variable doesn't exist when $b$fitxy$b$ starts, Asymptote creates a new user variable and sets its initial value to 1.0. HOLDING PARAMETERS FIXED: Asymptote looks for the user variables $i$a0fixed$i$, $i$a1fixed$i$, ... , $i$aNfixed$i$ to determine if you want to hold any of the fitting parameters fixed. If you set one of these variables to 'true' (a non-zero value), Asymptote holds that parameter fixed during the fit. USING ERRORS (WEIGHTING EACH DATA POINT): Both polynomial fitting and general expression fitting use the values in the $i$e$i$ vector to constrain the fit. If you know the standard deviation of each point, store these values in the $i$e$i$ vector before fitting. With the $i$e$i$ vector you can weight each of the points differently in the fit. A smaller value in the $i$e$i$ vector means a greater weight is given to that point and a greater impact on the fit. To remove a point from the fit entirely, set its $i$e$i$ vector to a value much larger then the other values in the $i$e$i$ vector. If the $i$e$i$ vector contains zero or negative values, Asymptote asks you if you want to give all the points equal weight. If you don't know the errors of your data points, use rpn 1 >e to fill the $i$e$i$ vector with a constant value of 1.0 for each point. When the $i$e$i$ vector is 1.0 for all points, Asymptote automatically multiplies the fit errors $i$a0sig$i$, $i$a1sig$i$, ..., $i$aNsig$i$, by sqrt[chisq/(npts - nParameters)]. Essentially this assumes that the fit is a good fit. Remember that if you don't know the errors in your data points, the value of chisq is meaningless. PLOTTING EACH ITERATION: To help you view the progress of the fit, set the user variable $i$plot_each_fit$i$ to true before you execute $b$fitxy$b$. With $i$plot_each_fit$i$ set to true, Asymptote plots the fitted function on your graph with each iteration. When $b$fitxy$b$ finishes, Asymptote restores the graph to the way it looked before $b$fitxy$b$ started. Plotting each iteration is a good way to monitor the progress of the fit and to judge how good your initial guesses were. If the user variable $i$plot_each_fit$i$ doesn't exist before $b$fitxy$b$ starts, Asymptote creates the variable and sets it to true. FIT RESULTS: After $b$fitxy$b$ executes, Asymptote sets the user variable chisq to the final chi square of the fit. It sets the user variables $i$a0$i$, $i$a1$i$, $i$a2$i$, ..., $i$aN$i$ to the estimated parameter values. Asymptote stores an estimate of the error of each parameter (diagonal elements of the covariance matrix) in the user variables $i$a0sig$i$, $i$a1sig$i$, ... , $i$aNsig$i$. It also sets the variable converged to true or false depending on whether $b$fitxy$b$ converged to a best fit and sets the variable iterations to the number of iterations that were completed. IF YOUR FIT PRODUCES UNDESIRABLE RESULTS: If you aren't able to obtain a satisfactory fit, try the following: 1. Check to see that the function is a good model of your data. Set $i$plot_each_fit$i$ to true before fitting to see if the function you are trying to fit adequately represents your data. 2. Try changing the initial values of the fit parameters. Don't use 0.0 for initial guesses. Use 0.1 or 0.0001 instead. Plot your initial guesses to see if they are reasonable or set $i$plot_each_fit$i$ to true before fitting. 3. Make sure all the coefficients of your function are distinguishable. You should not be able to algebraically combine two parameters into one. For example, if a function contains two constants or two identical terms, you can combine them as one. 4. Make sure that the best value for any parameter in your model is not infinity. FITTING ERRORS: (1) SINGULAR MATRIX: The most common error message when fitting an arbitrary function to your data is "Singular Matrix." Usually this happens when the function you are fitting does not have a unique solution. If Asymptote reports a singular matrix error, first try the steps above; then check to make sure that changing each parameter of the function has some effect on the fitting function. (2) OVERFLOW, UNDERFLOW or DIVIDE BY ZERO: Asymptote may encounter a numerical error such as an overflow, underflow or a division by zero when it evaluates the fitting function and its partial derivatives. Because Asymptote uses extended double precision for all of its computations, this usually does not happen unless the fitting process has arrived at extreme values. It can happen however, if the function has singularities in the range of x values. After trying the steps above, try shifting or scaling the values in the x vectors to values near zero. SEE ALSO: $b$rpn$b$ $b$plotline$b$ EXAMPLES: % Polynomial fitting: readcol x 1 % read x data readcol y 2 % read y data pointsymbol 4 cross plotpoints % plot the input data readcol e 3 % read the errors of the points ploterrors top % plot vertical error bars in both directions ploterrors bottom fitxy 2 % calculate a quadratic fit rpn <x 2 y^x a2 * <x a1 * + <a0 + >y % calculate y = a0 + a1 x + a2*x^2 plotline % plot the result as a line title Fit Results: a0 = \a0, a1 = \a1, a2 = \a2 % Fitting a Gaussian: datafile mydata readcolumn x 1 readcolumn y 2 readcolumn e 3 graphlimits plotpoints % Estimate initial values: set a0 5 % constant set a0fixed no set a1 0.01 % slope set a1fixed no set a2 10 % gaussian 1 center set a2fixed yes % Fix the value of the center set a3 4 % gaussian 1 width set a3fixed no set a4 100 % gaussian 1 amp set a4fixed no set plot_each_fit yes % Plot each iteration of the fit % Fit the data: fitxy 5 a0 x a1 * + x a2 - a3 / 2 y^x -1 * e^x a4 * + % Calculate the fit: rpn a0 <x a1 * + <x a2 - a3 / 2 y^x -1 * e^x a4 * + >y % And plot the fit: plotline $$fontname fontname Set the font for graph labels ARGUMENTS: fontname ± the name of the new graph font DESCRIPTION: Use $b$fontname$b$ to select the font for drawing graph labels. Select Set>Font to view a list of the fonts installed in your system. Asymptote uses the current value of the scale factor (set with the $b$scale$b$ command) when drawing the labels. A scale factor of 1 produces characters at the default size set with $b$fontsize$b$. Asymptote also rotates all labels (except for the title, and the $i$x$i$ and $i$y$i$ axis labels) by the amount you specify with the $b$rotation$b$ command. A rotation of 0 degrees produces labels parallel to the $i$x$i$ axis. You can rotate labels through any angle, but only labels rotated by 0, 90, 180, or 270 degrees will print on all printers. Asymptote draw labels rotated by angles other than 0, 90, 180 or 270 degrees as gray rectangles. This is called ¾greeking.à Greeked labels only print correctly on PostScript printers. SEE ALSO: $b$fontsize$b$ $b$scale$b$ $b$rotation$b$ $b$drawframe$b$ $b$drawlabel$b$ $b$drawxlabel$b$ $b$drawylabel$b$ $b$drawtitle$b$ $b$plotlabels$b$ $b$pencolor$b$ $b$textmode$b$ EXAMPLES: fontname Helvetica % set the font for labels and text to helvetica fontsize 12 % make 12 pt the default scale 2.0 % draw letters at 24 pt drawlabel center This is a test label in Helvetica 24 pt fontname Times rotation 45 drawlabel left I'm a Times labels rotated by 45¡ $$fontsize points Set the point symbol to use when drawing points ARGUMENTS: points ± text size when scale = 1.0 (in points) Use $b$fontsize$b$ to set the size (in points) that you want Asymptote to use for labels when the scale factor is set to 1.0. The $b$fontsize$b$ command is a handy way to adjust the size of your labels without having to change $b$scale$b$ every time you draw text. The default text size is 12 points. Put the $b$fontsize$b$ command in your Start Up script if you want to change this default. SEE ALSO: $i$graphics environment$i$ $b$drawframe$b$ $b$drawlabel$b$ $b$drawxlabel$b$ $b$drawylabel$b$ $b$drawtitle$b$ $b$plotlabels$b$ EXAMPLES: pointsize 6 % set the point size to 6 points scale 1 plotpoints % draw points that are 6 points in diameter scale 2 plotpoints % draw 12 pt points $$for variable from start to stop [ by step ] do command Repeat a command while incrementing or decrementing a variable ARGUMENTS: variable ± the user variable to increment or decrement start ± an expression for the starting value end ± an expression for the ending value step ± an expression for the amount to increment or decrement with each step command ± the command to execute each time through the loop DESCRIPTION: Use $b$for$b$ to repeat a command over and over again while Asymptote increments or decrements a user variable. You can use the value of the user variable in a script to read data from a sequence of numbered data files or to run a sequence of numbered scripts. Following the $b$for$b$ command, you must specify the name of the user variable you want to loop. If there is no user variable with the name you specify, Asymptote automatically creates one for you. Next, type the word ¾fromà followed by an expression for the starting value of the variable. After the starting value expression, type ¾toà followed by an expression for the ending value of the variable. These expressions could simply be constants (for example, for i from 1 to 10). You can also use more complicated expressions involving other variables or constants (for example, for i from j 2 + to k 1 -). Following the ending expression, you can (optionally) specify a step expression that Asymptote uses to increment or decrement the user variable. To specify a step expression, follow the stop expression by the word ¾byà followed by the step expression. For example, for i from 100 to 0 by˚-1 steps the variable i down from 100 to 0 in steps of -1. If you don't specify a step expression, Asymptote uses the expression 1 to increment the variable by 1 each time through the loop. Finally, type ¾doà followed by the command you want to execute each time through the loop. You can pass arguments to the command on the rest of the line. SEE ALSO: $b$if$b$ $b$while$b$ $b$repeat$b$ EXAMPLES: % A simple loop: for i from 1 to 10 do myScript % Step myVal from 10 to 0 by 1 and execute nextGraph: for myVal from 10 to 0 by -1 do nextGraph % Step i from 1 to 64 by powers of 2 for i from 1 to 64 by i 2 * do nextpower i % Stop looping when i > j for i from 0 to j do myLoop $$fullscreen [ on/off ] Expand the $i$Graph Window$i$ to fill the full screen ARGUMENTS: on/off ± if true, expand the $i$Graph Window$i$ to fill the screen and hide the menus else, shrink the $i$Graph Window$i$ back to its original size and show the menus DESCRIPTION: Use $b$fullscreen$b$ to turn Asymptoteàs full screen mode on or off. Full screen mode is useful if you are taking pictures of the screen or making a presentation. When you turn full screen mode on, Asymptote hides the menu bar and expands the graph to fill the entire screen. When you turn full screen mode off, Asymptote shrinks the $i$Graph Window$i$ back to its original size and makes the menu bar visible again. To toggle between these two modes, issue the $b$fullscreen$b$ command without an argument. If you specify the full screen mode you want, you may find it convenient to use the Asymptote constants ¾onà and ¾offà. All of Asymptoteàs features function normally in full screen mode. If you type something with the keyboard, Asymptote makes the $i$Command Window$i$ visible. You can then type the rest of the command and execute it. Even though the menu bar is not visible in full screen mode, you can still issue menu commands. Simply type the command key equivalent of a command or type command-.(period). Asymptote makes the menu bar visible and executes the command. To hide the menu bar again, type fullscreen on in the $i$Command Window$i$. While you are in full screen mode you can scroll and zoom the graph with the mouse. This is a handy way to position the graph exactly as you want it positioned. Hold down the option key and click and drag on the graph to scroll it. Hold down the command key and click to zoom in. Hold down the command and option keys together and click to zoom out. To zoom the graph to display the graph frame or the entire page, use $b$showgraph$b$ or $b$showpage$b$. To zoom the graph to a particular zoom factor, you can type $b$zoomgraph$b$ in the $i$Command Window$i$. The background in the $i$Graph Window$i$ is normally white. If you are taking pictures of the screen or making a presentation, you may want to use $b$backcolor$b$ to change the background color of the $i$Graph Window$i$. SEE ALSO: $b$showgraph$b$ $b$showpage$b$ $b$zoomgraph$b$ $b$backcolor$b$ EXAMPLES: backcolor 80 80 80 % set the background color to a light gray fullscreen on % expand the $i$Graph Window$i$ to full screen fullscreen % toggle between full screen mode on or off fullscreen off % turn full screen mode off and display the menu bar $$graphaspect ratio Set the aspect ratio of the graph ARGUMENTS: ratio ± the aspect ratio, y scale = ratio * $i$x$i$ scale DESCRIPTION: Use $b$graphaspect$b$ to fix the aspect ratio of the $i$x$i$ and $i$y$i$ axes. The $b$graphaspect$b$ command is particularly useful when you are making log-log graphs and want the number of decades per inch on the $i$x$i$ and $i$y$i$ axes to agree. When the scale of the $i$x$i$ and $i$y$i$ axes is the same, the aspect ratio is 1 and the slope, a, of a line on your graph (y = a*x) is also the exponent in the power-law that relates $i$x$i$ and $i$y$i$ (y = xa). The $b$graphaspect$b$ command is also useful when you are creating linear graphs and want them to have a square grid. When you use $b$graphaspect$b$ to set the aspect radio of your graph to 1, the $i$x$i$ and $i$y$i$ axes have the same number of tick marks per inch and $b$drawgrid$b$ produces a square coordinate grid. Note that $b$graphaspect$b$ works by adjusting the size of the graph frame, not the limits of your graph. Before you use $b$graphaspect$b$, you must set the limits of your graph with $b$graphlimits$b$ and position the graph frame on the page with $b$graphframe$b$. When you issue the $b$graphaspect$b$ command, Asymptote adjusts the width or the height of the graph frame so that the aspect radio is the ratio you specified. Asymptote also tries to make the new frame fit inside the old. Now you are ready to draw the axes of the graph with $b$drawframe$b$ or $b$drawaxis$b$ and plot your data. SEE ALSO: $b$graphlimits$b$ $b$graphframe$b$ $b$graphunits$b$ $b$graphticks$b$ $b$drawframe$b$ $b$drawaxis$b$ EXAMPLES: graphlimits 5 25 -10 10 % set the graph limits graphaspect 1.0 % make the y axis scale the same as x drawframe graphticks -1 0 -1 0 % use log-log tick marks graphlimits 0 5 1 4 % 1 to 105 in x; 10 to 104 in y graphaspect 1.0 % plot the same number of decades per inch drawframe % on the x and y axes graphlimits 0 100 0 100 graphaspect 2.0 % make y have twice the scale as x $$graphframe gleft gright gbottom gtop Set the position of the graph frame on the page ARGUMENTS: gleft ± left side of the frame in page coordinates gright ± right side of the frame in page coordinates gbottom ± bottom of the frame in page coordinates gtop ± top of the frame in page coordinates DESCRIPTION: Use $b$graphframe$b$ to position the graph frame on the page. The $b$graphframe$b$ command uses page coordinates with the origin (0,0) in the lower left of the page. You can use $b$graphunits$b$ to choose which units you want to use for page coordinates (inches, cm, or points). Keep in mind that the dimensions of the page are stored in the Asymptote variables \pleft, \pright, \pbottom and \ptop. You can use these to specify the position of the graph on the page. For example, to set the graph frame to fill the page with a 1 inch margin use the following commands: graphunits in graphframe pleft 1 + pright 1 - pbottom 1 + ptop 1 - drawframe SEE ALSO: $i$Variables$i$ $b$graphunits$b$ $b$drawframe$b$ $b$drawaxis$b$ EXAMPLES: graphframe ? % choose the graph frame interactively graphunits cm graphframe 5 5 15 15 % a 10 cm by 10 cm graph graphunits inches graphframe 2 2 ptop 2 - pright 2 - % draw a graph with a 2 inch margin % Shift the graph frame up by the current height of the graph plus one inch: graphunits inches set vertoffset gtop gbottom - 1 + graphframe vertoffset gbottom + gleft vertoffset gtop + gright drawframe inside nolabels nolabels nolabels nolabels $$graphlimits [ xleft xright ybottom ytop ] Set the limits of the graph ARGUMENTS: xleft ± x value at left side of the graph xright ± x value at right side of the graph ybottom ± y value at bottom of the graph ytop ± y value at the top of the of the graph DESCRIPTION: Use $b$graphlimits$b$ to set the $i$x$i$ and $i$y$i$ limits of your graph. Asymptote uses these limits for all subsequent plotting and drawing. To have Asymptote choose the limits of your graph for you, use $b$graphlimits$b$ command without arguments. Asymptote chooses limits that make all the points visible. To set the limits of the graph you must specify all four arguments to the $b$graphlimits$b$ command. The first and second arguments are the $i$x$i$ values at the left and right sides of the graph frame. The third and fourth arguments are the $i$y$i$ values at the bottom and top of the frame. If you want the $i$x$i$ or the $i$y$i$ axis to run 'backward' (increasing from left to right or increasing from top to bottom) just specify the larger axis limit first. See the example below. If you want to specify the limits for one axis, but have Asymptote choose the limits of the other axis for you, specify 0 0 for the limits of the axis you want Asymptote to adjust. For example, if you type the command graphlimits 3 4 0 0 Asymptote sets the $i$x$i$ axis to range from 3 to 4 and chooses the $i$y$i$ axis limits automatically. SEE ALSO: $b$drawframe$b$ $b$drawaxis$b$ EXAMPLES: graphlimits % set the limits automatically for both x and y graphlimits 2 5 2.4 9 % set x limits to range from 2 to 5 and y from 2.4 to 9 graphlimits 0 0 1 12 % choose x automatically, set y limits to 1 to 12 graphlimits % choose limits automatically graphlimits 0 xright ybottom ytop % then fix xleft to be 0.0 graphlimits 1 -1 0 10 % x runs 'backward' from 1 to -1; y from 0 to 10 graphlimits % first have Asymptote choose limits graphlimits xleft xright ytop ybottom % then flip the y axis 'upside down' $$graphticks [ xminor xmajor yminor ymajor ] Set the spacing of major and minor tick marks ARGUMENTS: xminor, yminor ± spacing for minor tickmarks in graph coordinates xmajor, ymajor ± spacing for major tickmarks in graph coordinates DESCRIPTION: Use $b$graphticks$b$ to set the intervals for major and minor tick marks. ¾Minorà refers to the interval between small tick marks and ¾majorà refers to the interval between large tick marks. To have Asymptote choose the tick spacing for you, use $b$graphticks$b$ with no arguments. Specify 0 for xmajor or ymajor to have Asymptote choose the tick spacing of one axis while you specify the tick spacing of the other. To draw logarithmic minor tick marks and major tick marks at each decade, set xminor or yminor to a negative value. For example, use xminor = -1 and xmajor = 0 to draw a logarithmic $i$x$i$ axis and let Asymptote choosing the spacing for the major tick spacing (about one major tick every inch). To specify the tick spacing directly, set xminor to the spacing in decades for minor tick marks and xmajor to the number of decades between major tick marks. For example, use xminor = -0.5 and xmajor = -2 to draw minor ticks every half decade and major tick marks every 2nd decade. When you plot log-log graphs, Asymptote plots the values in the $i$x$i$ and $i$y$i$ vectors directly and doesnàt take the logarithm of them before plotting the points. When you make a log-log or log-linear graph, use $b$rpn$b$ to calculate the replace the values in you $i$x$i$ and $i$y$i$ vectors before plotting them. SEE ALSO: $b$graphlimits$b$ $b$drawframe$b$ $b$drawaxis$b$ $b$drawgrid$b$ $b$rpn$b$ EXAMPLES: graphticks .5 1 20 100 % small x ticks every .5 units of x, big ticks every 1 in x % small y ticks every 20 units of y, big ticks every 100 readcol x 1 readcol y 2 rpn <x log >x % replace the x values with their logs rpn <y log >y % do the same for y graphlimits 1 3 -1 1 % x decades from 1 to 3, y from decades -1 to 1 graphticks -1 0 -1 0 % log ticks on both axes drawframe readcol x 1 readcol y 2 rpn <y log >y % calculate log of y graphlimits 1 3 -1 1 % x runs from 1 to 3 % y limits from 10^-1 to 10^1 graphticks 0 0 -1 0 % choose x ticks automatically, y ticks are logarithmic drawframe graphticks ? % choose tick spacing via a dialog box $$graphunits unitname Set the units for measuring page coordinates ARGUMENTS: unitname ± unit name (inches, centimeters, or points) DESCRIPTION: Use $b$graphunits$b$ to specify the units you want to use for page coordinates. Specify either 'inches,' 'cm' or 'points' or the abbreviations 'in,' 'cm' or 'pts.' After you change the units with $b$graphunits$b$, all subsequent commands that take page coordinates as arguments (for example $b$graphframe$b$) assume that arguments you give them are in the new units. The Status and Variables Windows also display all quantities in page coordinates using the units you have specified with $b$graphunits$b$. SEE ALSO: $i$Constants$b$ $b$graphframe$b$ EXAMPLES: graphunits cm graphunits inches graphframe 2 4 4 8 % 2 to 4 inches in x, 4 to 8 inches in y drawframe $$help [ command ] TO USE ASYMPTOTE'S ON-LINE HELP: ¥ Type 'help' in the $i$Command Window$i$: ¥ To get help on a particular command, type help commandName ¥ To get help on a menu command or window: Press the command (clover leaf) and ? keys together to activate help cursor. Then, select a menu command or click a window with the mouse. ¥ Select a help topic from the Help menu under the Apple Menu ¥ Select ¾Helpà from the Window menu Window>Help or type command-H ¥ Click the Help button when an error message appears. <<< Click on the scroll bar for more information <<<<<<<<<< Use the left and right arrow keys in the lower left corner of this window to move between entries in the help file. Each help entry has a title (usually a command name) followed by a list of arguments. Optional arguments are enclosed in square brackets []. For a complete description of how to use on-line help file, see the section titled ¼Using the Help Window½ in Chapter 3 of the Asymptote Useràs Guide. $$hidewindow [ windowname ] Make a window invisible ARGUMENTS: windowname ± the name of the window to hide DESCRIPTION: Use $b$hidewindow$b$ to make a window invisible and reduce screen clutter. You can also hide a window by clicking on its close box while holding down the option key. To make a hidden window visible again, use $b$showwindow$b$ or select the window from the $i$Windows menu$i$. Hiding a window does not release the memory is occupies. To close a window and release the memory it occupies, use $b$closewindow$b$ rather than $b$hidewindow$b$. If you donàt specify the window you want to hide, Asymptote hides the currently active window. You can also use \f and \r to hide the Data and Recorder Windows respectively. SEE ALSO: $b$showwindow$b$ $b$closewindow$b$ EXAMPLES: hide % hide this window set test ?You can't see me! show % make this window visible again hidewindow test data % make the window 'test data' invisible hidewindow \f % hide the current data file window hidewindow \r % hide the current Recorder Window $$if expression then command1 [ else command2 ] Execute a command based on the result of a logical test ARGUMENTS: expression ± a logical expression resulting in a single value which is either true (›0) or false (=0) command1 ± the command or macro to execute if the expression is true command2 ± the command or macro to execute if the expression is false DESCRIPTION: Use the $b$if$b$ command to control the execution of your scripts based on logical tests. For example, if you want to draw the $i$x$i$ and $i$y$i$ points as filled squares only if the number of points is greater than 100, you could use: if npts 100 > then pointsymbol 4 filled plotpoints In this example, Asymptote puts the number of points (npts) and the constant 100 on the arguments stack. It then compares them with the > operator to produce a result that is either true (1) or false (0). If the result is true, Asymptote executes $b$pointsymbol$b$ to set the point symbol to filled squares. The logical operators you can use in $b$if$b$ expressions are: < less than > greater than = equal <= less than or equal to >= greater than or equal to <> not equal Remember, you don't have to use a logical operator in every expression. Asymptote simply evaluates the expression and tests to see if it is true (›0) or false (=0). Your logical expression must be followed with the word 'then' followed by a command or macro name. Optionally, you can follow the command with the keyword 'else' and an alternate command to be executed if the logical expression is false. For example the command if x(10) 34.9 / 10 < then script1 else script2 executes 'script1' if x(10)/34.9 is less than 10; otherwise 'script2' is executed. SEE ALSO: $b$rpn$b$ $b$repeat$b$ $b$while$b$ EXAMPLES: % Draw filled squares if the variable 'drawsquares' is true, else draw open triangles: if drawsquares then pointsymbol 4 filled else pointsymbol 3 open % If the left axis limit is less than 100, set it to be 100 and leave the rest of the % axis limits unchanged. if xleft 100 < then graphlimits 100 xright ybottom ytop $$moveto x y Move the graph pen to a new x, y coordinate (in graph coordinates) ARGUMENTS: x ± x coordinates of new pen position y ± y coordinates of the new pen position DESCRIPTION: Use $b$moveto$b$ to move the graph pen to a new position on your graph. The coordinates you specify are measured in graph coordinates. Remember that $b$moveto$b$ only positions the pen; it doesn't draw on the graph. Use $b$drawto$b$ if you want to draw a line from the old pen position to the new position. To move the graphics pen using the graph cursor, type moveto ? in the $i$Command Window$i$, or select Plot>Move To. Asymptote activates the graph cursor which you can use to specify the new pen position. When you click the mouse, Asymptote enters the $b$drawto$b$ command in your $i$Recorder Window$i$. Using the graph cursor this way is particularly useful when you are placing labels on your graph. SEE ALSO: $b$drawto$b$ $b$cursor$b$ $b$graphlimits$b$ EXAMPLES: moveto 2.0E10 1929.2 % move to (x, y) = (2E10, 1929.2) on the graph moveto ? % position the pen interactively with the mouse moveto xleft xright + 2 / ybottom ytop + 2 / % move to the center of the graph moveto x(10) y(10) 5 + % position the pen 5 units of y above the 10th point drawlabel left This is point #10 moveto ? % get the starting position of a line drawto ? % draw to a line to this position drawarrowto ? % draw and arrow to the next position moveto ? % move to the starting position repeat 10 times drawto ? % draw 10 connected line segments with the mouse $$moviefile [ filename ] Open a new or existing movie file in the $i$Movie Window$i$ ARGUMENTS: filename ± the name of the movie file to open DESCRIPTION: To create a new, empty movie file, use $b$moviefile$b$ without an argument. When you create a new movie, Asymptote uses the current size of the $i$Graph Window$i$ for the dimensions of the movie. To create a movie with a different size, resize the Graph Window to the size you want before you create a new movie. To open an existing movie file, specify the movie fileàs name after the $b$moviefile$b$ command. Asymptote opens movie files in the $i$Movie Window$i$. You can play them using the controls as the bottom of the $i$Movie Window$i$. You can add a frame to the end of a movie with $b$movieframe$b$. To use the $b$moviefile$b$ command, you must install the QuickTime extension in your system. Follow the instructions in Appendix G to install QuickTime if the $b$moviefile$b$ command tells you that QuickTime is not installed. If you plan to create lots of movies, especially color movies, you may also want to use the Finder to increase amount of the memory allocated to Asymptote. SEE ALSO: $b$movieframe$b$ EXAMPLES: moviefile % create a new movie file on disk moviefile MyMovie % open the existing movie ¾MyMovieà in the Movie Window $$movieframe Add a frame to the end of the movie in the $i$Movie Window$i$ ARGUMENTS: none DESCRIPTION: Use $b$movieframe$b$ to copy the contents of the $i$Graph Window$i$ to a new frame at the end of the movie in the Movie Window. You can only use $b$movieframe$b$ after you have opened a movie with the $b$movieframe$b$ command. SEE ALSO: $b$moviefile$b$ EXAMPLES: movieframe % add a frame to the end of the movie in the Movie Window $$newwindow Open a new Text Editor Window ARGUMENTS: none DESCRIPTION: The $b$newwindow$b$ command, which is the same as selecting File>New, opens a new, untitled Text Editor Window. You can use the window to write a script or to enter data. To make the new window the $i$Recorder Window$i$, select its name in the File>Recorder menu. To make the new window the current $i$Data Window$i$, select its name in the File>Data menu. SEE ALSO: $b$closewindow$b$ $b$hidewindow$b$ $b$showwindow$b$ $i$Data menu$i$ $i$Recorder menu$i$ $$notation [ format ] Set the notation format labels ARGUMENTS: format ± a value indicating the notation format to use for labels decimal (=-2) float (=-1) general (= 0) default (= 1) scientific (= 2) hhmmss (= 3) ddmmss (= 4) (see examples below) DESCRIPTION: Use the $b$notation$b$ command to select what notation scheme Asymptote should use when converting numbers into labels. The $b$notation$b$ and $b$digits$b$ commands work together to select the format and the number of digits that should be displayed. If you want to have Asymptote convert numbers to labels automatically, use digits 0 notation general If you want greater control over how many decimal places to use or want to force Asymptote to use a particular notation, then specify $b$notation$b$ and $b$digits$b$ before you draw a label. Asymptote uses the current value of $b$digits$b$ when it draws labels which contain variables or constants. For most notation formats $b$digits$b$ selects the number of significant digits you want to display in the number. Use $b$digits$b$= 0 if you want to show all the digits in a number. For the 'decimal' notation ($b$notation$b$ = -2), $b$digits$b$ specifies how many digits should be printed $i$after$i$ the decimal point. With 'decimal' notation set $b$digits$b$ to a large number (say >10) if you want to show all digits. The following examples show how Asymptote converts the value 123.456789 to a label using a variety of notation formats. $b$notation$b$ $b$digits$b$ Label decimal 4 123.4568 2 123.46 0 123 For the ¾decimalà notation, $b$digits$b$ is the number of digits to display after the decimal point. If the value is 0, the ¾decimalà notation displays ¼0.0½ unless $b$digits$b$ is 0, in which case a ¼0½ with no decimal point is displayed. $b$notation$b$ $b$digits$b$ Label float 4 123.5 2 123 0 123.456789 For the ¾floatà notation, $b$digits$b$ is the number of significant digits to display. The float notation always displays ¼0½ if the value is 0. $b$notation$b$ $b$digits$b$ Label general 4 123.5 2 123 0 123.456789 The ¾generalà format uses ¾scientificà notation if the value is greater than 1˚x10^6, otherwise the ¾floatà notation is used. The general notation always displays ¼0½ if the value is 0. The ¾defaultà notation always uses scientific notation: $b$notation$b$ $b$digits$b$ Label default 4 1.235˚x˚10^2 2 1.2˚x˚10^2 0 1.23456789˚x˚10^2 For the ¾defaultà notation, $b$digits$b$ is the number of significant digits in the mantissa. The default notation always displays ¼0½ if the value is 0. The ¾scientificà notation uses scientific notation: $b$notation$b$ $b$digits$b$ Label scientific 4 1.235˚x˚10^2 2 1.2˚x˚10^2 0 1.23456789˚x˚10^2 For the ¾scientificà notation, $b$digits$b$ is the number of significant digits in the mantissa. If the value is 0 and $b$digits$b$is 0, ¾scientificà notation displays ¼0½, otherwise ¼0.0½ is displayed. The ¾hhmmssà notation displays hour, minutes and seconds: $b$notation$b$ $b$digits$b$ Label hhmmss 4 123h 27m 24.4s 2 123h 27m 0 123h 27m 24s For the ¾hhmmssà notation, if $b$digits$b$ is 0, the time is displayed with no decimal point in the seconds portion. If $b$digits$b$ is 1, only the hours are displayed. If $b$digits$b$ is 2, the hours and minutes are displayed. If $b$digits$b$ is >3, $b$digits$b$ - 3 is the number digits to display after the decimal point in the seconds portion of the label. If the value is 0, ¼0h½ is always displayed. The ¾ddmmssà notation displays degrees, minutes and seconds: $b$notation$b$ $b$digits$b$ Label ddmmss 4 123¡27à 24.4àà 2 123¡ 27à 0 123¡ 27à 24àà For the ¾ddmmss notation, if $b$digits$b$ is 0, the angle is displayed with no decimal points in the seconds portion. If $b$digits$b$ is 1, only the degrees are displayed. If $b$digits$b$ is 2, the degrees and minutes are displayed. If $b$digits$b$ is >3, $b$digits$b$ - 3 is the number digits to display after the decimal point in the seconds portion of the label. If the value is 0, ¼0¡½ is always displayed. SEE ALSO: $b$digits$b$ $b$drawlabel$b$ $b$drawtitle$b$ $b$drawxlabel$b$ $b$drawylabel$b$ $b$drawlabel$b$ EXAMPLES: notation scientific digits 4 drawlabel left x(1) % if x(1)= 34.373 label = 3.437 x 10^1 $$npts [ n ] Set the number of points to plot or calculate ARGUMENTS: n ± the number of points to plot or use in calculations DESCRIPTION: Use $b$npts$b$ to set the length of the $i$x$i$, $i$y$i$, $i$p$i$, $i$e$i$ and label vectors. When you read data with $b$readcolumn$b$ or $b$readrow$b$, Asymptote automatically sets npts to the number of points it read. You can use $b$npts$b$ when you are going to calculate values using the $b$rpn$b$ calculator. With $b$npts$b$, you can choose the number of points to calculate. If you donàt specify the number of points you want, Asymptote sets the number of points to the maximum possible. Note that changing $b$npts$b$ does not change the amount of memory devoted to Asymptoteàs vectors. Changing $b$npts$b$ changes the number of points that commands like $b$plotline$b$ use when plotting data. To change the maximum length of Asymptoteàs vectors use File>Options>Memory˚Use. SEE ALSO: $b$rpn$b$ $b$datalines$b$ $b$readcolumn$b$ $b$readrow$b$ $i$Options$i$ $i$Memory Use$i$ EXAMPLES: % Calculate y= x*x for x= 1 to 100 npts 100 rpn index >x dup * >y % index puts the numbers 1 through 100 on the stack $$pagesetup Adjust the page setup ARGUMENTS: none DESCRIPTION: Use the $b$pagesetup$b$ command to read the orientation of the page (landscape or portrait) and other page setup information from the current script. To save the page setup information with a script, first select the script from the File>Recorder menu to make it the current Recorder. Next, choose File>Graph˚Page˚Setup and configure the graph page setup. To save the page setup to the current Recorder, select File>Graph˚Page˚Setup>Save˚to˚Recorder. To read the graph page setup information from your script, add the command pagesetup to the script. When Asymptote encounters the $b$pagesetup$b$ command as it executes the script, it reads the previously saved page setup information as if you had chosen File>Graph˚Page˚Setup from the $i$File$i$ menu. Remember that when you change the graph page setup information, Asymptote clears the graph and erases the contents of the $i$Graph Window$i$. As a result, you should put the page setup command at the beginning of your script $i$before$i$ you begin drawing your graph. SEE ALSO: $b$print$b$ $i$File Menu$i$ $i$Graph Page Setup$i$ $i$Save to Recorder$i$ EXAMPLES: pagesetup % Read the graph page setup from the Recorder DoPlot % Then create the graph by running the script ¾DoPlotà print % Print the graph $$pencolor r g b or colorName Set the pen color for graphics and text ARGUMENTS: r, g, b ± red green blue color values in percent or colorName ± the name of a color (red, green, blue, magenta, yellow, purple, black, white) DESCRIPTION: Use $b$pencolor$b$ to change the pen color. There are two ways you can specify the color you want. The first is to specify a color by name as in this example: pencolor red For greater control, you can also specify a combination of red, green and blue that produces the color you want. For example, to change the pen color to red use pencolor 100 0 0 You can specify any color you want by its red, green, and blue component intensities. A handy way to choose the pen color is to use Asymptoteàs color wheel. To use the color wheel, type pencolor ? Or select Set>Pen>Color. Asymptote displays a color wheel so you can select the color you want. When you click OK, Asymptote adds the $b$pencolor$b$ command followed by the red, green and blue intensities of the color you selected in your Recorder script. SEE ALSO: $b$penpattern$b$ $b$pensize$b$ $b$pendash$b$ $b$fillpattern$b$ $i$Variables and Constants$i$ EXAMPLES: pencolor 50 50 50 % gray drawframe % draw a gray frame pencolor 10 90 25 % a particular color pencolor ? % Choose a color using a color wheel. Put this command % in a script to open the color wheel every time it runs. % If you type this command in the $i$Command Window$i$, Asymptote displays % the color wheel. When you click OK, Asymptote adds the pencolor % command followed by the r, g, b values of the color you selected % to your Recorder script. $$pendash [ on1 [ off1 ] [ on2 off2 ] [ on3 off3 ] ] Set the pen dash pattern (solid, dashed, dotted, etc.) ARGUMENTS: n ± dash pattern lengths (none, 1, 2, 4 or 6 are expected) on1 = length of 1st ON segment off1 = length of 1st OFF segment on2 = length of 2nd ON segment off2 = length of 2nd OFF segment on3 = length of 3rd ON segment off3 = length of 3rd OFF segment DESCRIPTION: Asymptote uses the current pendash pattern when it draws points and lines (except when drawing axes). If you don't specify a dash pattern, a solid line is used. You specify the dash pattern by telling Asymptote the lengths of 6 line segments that make up the pattern. The 1st, 3rd and 5th segments are the ¾onà part of the dash pattern, while the 2nd, 4th and 6th segments are the lengths of the white space in between. You donàt have to specify all of the segments if you donàt want to. If you provide only one segment length, Asymptote uses it for all six segments. If you want to repeat two segments over for the whole pattern, simply specify the on and off segments you want to use. You can use the Asymptote constants $i$solid$i$, $i$dot$i$, $i$short$i$ and $i$long$i$ to specify the dash pattern segments. For example: pendash short % short dashed lines spaced by a short line segment pendash long % same thing but long dashed with long spaces pendash long short % long dashes spaced by short segments SEE ALSO: $b$pensize$b$ $b$pencolor$b$ $b$penmode$b$ $i$Variables and Constants$i$ EXAMPLES: pendash dot % draw all subsequent lines as dotted lines pendash % use solid lines pendash ? % choose a dash pattern graphically pendash long dot dot short short short % a dash pattern with all 6 segments specified pendash 2 1 2 1 4 1 % a particular dash pattern $$penmode [ n ] Set the pen transfer mode for drawing graphics ARGUMENTS: n ± the new pen mode number (1 through 8) or ± a mode name (opaque, transparent, reversed, erase inverted, overlay, clear, whiteout) DESCRIPTION: Use the $b$penmode$b$ command to select a pen drawing mode. The pen mode is a number from 1 to 8. For convenience you can use one of the following constants to specify the mode you want: opaque, transparent, reversed, erase, inverted, overlay, clear, whiteout. To choose a mode graphically type: penmode ? or select Set>Pen>Mode. Asymptote displays a dialog box with an illustration of each pen mode. Click the pen mode you want with the mouse. ¥ Note: PostScript printers don't make use of pen transfer modes. This is a feature of the LaserWriter driver supplied by Apple. You can only use pen modes on printers that are QuickDraw-based. SEE ALSO: $i$Variables and Constants$i$ $b$pencolor$b$ $b$pensize$b$ $b$pensize$b$ $b$pendash$b$ $b$penmode$b$ EXAMPLES: penmode reversed drawpoint % to reverse the pen color where the dot is drawn. $$penpattern [ penpattern ] Set the pen pattern to use when drawing lines ARGUMENTS: penpattern ± a pattern number (0 through 38) or ± a pattern name (none , black, darkgray, gray, lightgray, white, grid, vertical, horizontal, diagonal, white, bricks) DESCRIPTION: Use $b$penpattern$b$ to choose the pattern for pen drawing. The pen pattern is a number between 0 and 38. For convenience you can specify one of these named patterns: none, black, darkgray, gray, lightgray, white grid, vertical, horizontal, diagonal, white, bricks To choose the pattern for filling points and polygons, and for shading under curves, use the $b$fillpattern$b$ command. Remember, that although you can use $b$penpattern$b$ to draw dashed lines, it is better to use $b$pendash$b$ instead. Lines drawn with dash patterns are true dashed lines: the dash pattern follows the curve of the line. SEE ALSO: $i$Variables and Constants$i$ $b$fillpattern$b$ $b$pencolor$b$ $b$penmode$b$ $b$pensize$b$ $b$pendash$b$ EXAMPLES: % The following commands draw a big, fat, gray X on the graph penpattern gray pensize 10 moveto xleft ybottom drawto xright ytop moveto xleft ytop drawto xright ybottom penpattern gray fillpattern black pointsymbol 4 filled % Draw filled squares with a gray outline and a black center $$pensize size Set the pen size in points ARGUMENTS: size ± thickness of the pen in points DESCRIPTION: Use $b$pensize$b$ to set the thickness of the pen. Asymptote measures pen sizes in points (72 points = 1 inch). To draw hairlines on a LaserWriter, use a pensize of 0.25. To 'turn off' the pen, set the pensize to 0. This is useful if you want to draw filled polygons or points which arenàt outlined by the pen. SEE ALSO: $b$pencolor$b$ $b$pensize$b$ $b$pendash$b$ $b$penmode$b$ $b$penpattern$b$ EXAMPLES: pensize 3 % draw with a pen thickness of 3 pensize 1 % normal pen thickness (1 point) pensize .25 % hairline on a LaserWriter pensize 0 % hide the pen so it's not visible fillpattern gray plothistogram % draw a histogram with the pen turned off pensize 1 % restore the pen $$plotarrows Connect pairs of points with arrows or line segments ARGUMENTS: none DESCRIPTION: Use $b$plotarrows$b$ to plot arrows connecting pairs of points. To plot line segments (rather than arrows between the points) set $b$scale$b$ to 0.0 (with a scale factor of 0.0 Asymptote doesnàt draw arrow heads). To use $b$plotarrows$b$ first read the data and store the pairs of points on the calculator stack. For example, assume your data file has the ($i$x$i$, $i$y$i$) coordinates of the pairs of points arranged in 4 columns (columns 1 and 2 are $i$x$i$ and $i$y$i$ for the start of each line segment, and columns 3 and 4 are $i$x$i$ and $i$y$i$ for the end). To read these pairs of points and connect them with line segments use: readcolumn x 1 % read the starting (x,y) positions of the line segments readcolumn y 2 rpn <y <x % push the first pair of (x,y) points on the calculator stack readcolumn x 3 % Now read the end points of the lines: readcolumn y 4 rpn <y <x % push the (x,y) end points: plotarrows % draw lines that connect the pairs of points on the stack ¥ Note: If you perform other calculations on the stack, use File>Options>Memory˚Use to configure the calculator to hold more than four vectors. If you donàt, your calculations may roll off the top of the stack and get lost. Remember to set $b$cliptoframe$b$ to $i$true$i$ if you donàt want Asymptote to plot any pairs of points that extend outside the graph frame. SEE ALSO: $i$Memory Use$i$ $i$Options Menu$i$ $i$File Menu$i$ $b$readcolumn$b$ $b$readrow$b$ $b$pendash$b$ $b$penmode$b$ $b$pensize$b$ $b$pencolor$b$ $b$penpattern$b$ $b$plotline$b$ $b$plotpoints$b$ $b$plothistogram$b$ $b$ploterrors$b$ $b$cliptoframe$b$ $$ploterrors direction Use the e vector to draw error bars or arrows at each point ARGUMENTS: direction ± the direction of the error bar or limit bottom (=1) left (=2) top (=3) right (=4) DESCRIPTION: Use $b$ploterrors$b$ to draw error bars or limit arrows on your graph. First, read the length of the error bars into the $i$e$i$ vector or use $b$rpn$b$ to calculate the $i$e$i$ vector. Then, use $b$ploterrors$b$ to draw the error bar in the direction you want. To draw an arrow (to indicate a limit) rather than an error bar at a point, put a negative value in the $i$e$i$ vector for that point. Use $b$scale$b$ to adjust the size of the crosses or arrow heads on the end of the error bars. Set $b$scale$b$ to 0 if you don't want crosses or arrow heads. You can use $b$ploterrors$b$ repeatedly to draw error bars in all four directions from each point. Because you can read a different set of error bar data each time you use $b$ploterrors$b$, you can draw error bars with different lengths or limits in each of the four directions. This makes it possible to draw correct error bars on log-log or semi-log graphs. Remember to set $b$cliptoframe$b$ to $i$true$i$ if you donàt want your error bars to extend outside the graph frame. SEE ALSO: $b$scale$b$ $b$readcolumn$b$ $b$readrow$b$ $b$plotline$b$ $b$plotpoints$b$ $b$plothistogram$b$ $b$plotarrows$b$ $b$cliptoframe$b$ EXAMPLES: readcol x 1 % read the x and y data readcol y 2 graphlimits plotline readcolumn e 3 % read the error in x ploterrors right % plot the +x error bars ploterrors left % plot the -x error bars (same as +x) readcolumn e 4 % read positive y error ploterrors top % plot the +y direction error bars readcolumn e 5 % read negative y error ploterrors bottom % plot the -y direction errors (different than +y) ploterrors ? % Choose the direction graphically $$plothistogram [ level ] Draw the (x, y) points as a histogram ARGUMENTS: level ± the baseline level of the histogram DESCRIPTION: Use $b$plothistogram$b$ to draw the data in the $i$x$i$ and $i$y$i$ vectors as a histogram. If you need to calculate the histogram of your data first, use $b$binxy$b$ then issue the $b$plothistogram$b$ command. If your $i$x$i$ and $i$y$i$ data are not in order, you can use $b$sort$b$ before plotting the histogram. The optional argument to $b$plothistogram$b$ is the baseline level. If you specify the baseline, $b$plothistogram$b$ fills the area between the baseline level and the histogram using the current $b$fillpattern$b$ and $b$pencolor$b$. If you don't supply the baseline level, $b$plothistogram$b$ just draws the histogram and doesn't fill the area underneath. Remember to set $b$cliptoframe$b$ to $i$true$i$ if you donàt want Asymptote to draw parts of the histogram that may extend outside the graph frame. SEE ALSO: $b$binxy$b$ $b$sort$b$ $b$fillpattern$b$ $b$pencolor$b$ $b$plotline$b$ $b$plotpoints$b$ $b$ploterrors$b$ $b$plotarrows$b$ $b$cliptoframe$b$ EXAMPLES: readcol x 3 % read the data binxy 100 % calculate a histogram of 100 bins graphlimits % scale the graphlimits to fit it all in plothistogram % plot it without filling underneath drawframe plothistogram 0.0 % fill underneath the histogram with the current fill % pattern and color with a baseline of y= 0.0 $$plotlabels [ position ] Plot the labels in the label vector at each point ARGUMENTS: position ± the position of the labels relative to each point: aboveleft (=7) above (=8) aboveright (=9) centerleft (=4) center (=5) centerright (=6) belowleft (=1) below (=2) belowright (=3) DESCRIPTION: To plot labels at each ($i$x$i$, $i$y$i$) point, first read the labels into the $i$l$i$ vector with the $b$readcolumn$b$ or $b$readrow$b$ commands. Then, use $b$plotlabels$b$ and specify how you want Asymptote to position the labels relative to each point. You can use $b$fontname$b$ and $b$scale$b$ to choose the font and size of the labels and $b$rotation$b$ to rotate them about each point. Remember to set $b$cliptoframe$b$ to $i$true$i$ if you donàt want Asymptote to plot labels that lie outside the graph frame. SEE ALSO: $i$Variables and Constants$i$ $b$readcolumn$b$ $b$readrow$b$ $b$fontname$b$ $b$scale$b$ $b$rotation$b$ $b$plotline$b$ $b$plotpoints$b$ $b$plothistogram$b$ $b$ploterrors$b$ $b$plotarrows$b$ $b$cliptoframe$b$ EXAMPLES: readrow x 2 % read x, y and the labels from rows 2,3,4 of the data file readrow y 3 readrow l 4 fontname helvetica graphlimits plotlabels aboveleft % draw the labels plotpoints % draw the points drawframe % add a fame plotlabels ? $$plotline Plot a line by connecting the (x, y) data points ARGUMENTS: none DESCRIPTION: Use $b$plotline$b$ to connect your ($i$x$i$, $i$y$i$) points with a line. Like all other plotting commands, $b$plotline$b$ uses the current pen properties to draw the line. If your $i$x$i$ data are in a random order, you may want to use $b$sort$b$ in order to plot a line that moves from left to right or right to left in $i$x$i$. Remember to set $b$cliptoframe$b$ to $i$true$i$ if you donàt want Asymptote to plot segments of the line that extend outside the graph frame. SEE ALSO: $i$graphics environment$i$ $b$plotpoints$b$ $b$ploterrors$b$ $b$plothistogram$b$ $b$plotpolygon$b$ $b$plotlabels$b$ $b$pendash$b$ $b$penmode$b$ $b$pensize$b$ $b$pencolor$b$ $b$penpattern$b$ $b$sort$b$ $b$cliptoframe$b$ EXAMPLES: readcolumn x 2 % x data are in column 2 readcolumn y 3 % y data are in column 3 graphlimits % automatic limits plotline drawframe $$plotpoints Draw points at all (x, y) points ARGUMENTS: none DESCRIPTION: Use $b$plotpoints$b$ to plot a symbol at each ($i$x$i$, $i$y$i$) point. You can make the symbols larger or smaller with the $b$scale$b$ command, and you can rotate them with the $b$rotation$b$ command. Asymptote uses the current pen properties such as $b$pensize$b$, $b$pencolor$b$ and $b$penpattern$b$ when drawing the point symbols. The current $b$fillpattern$b$, if any, is the fill pattern Asymptote uses for filled points. To plot the same symbol at each point, use $b$pointsymbol$b$ to specify the symbol you want to plot. Alternatively you can plot different symbols at each point using information in your data file. To do this, see the description of how to read point symbols with $b$readcolumn$b$ or $b$readrow$b$. Remember that $b$cliptoframe$b$ must be set to $i$true$i$ if you donàt want Asymptote to plot any points that lie outside the graph frame. SEE ALSO: $b$readcolumn$b$ $b$readrow$b$ $b$pointsymbol$b$ $b$scale$b$ $b$rotation$b$ $b$pendash$b$ $b$penmode$b$ $b$pensize$b$ $b$pencolor$b$ $b$penpattern$b$ $b$fillpattern$b$ $b$plotline$b$ $b$plotpoints$b$ $b$plothistogram$b$ $b$ploterrors$b$ $b$plotarrows$b$ $b$cliptoframe$b$ EXAMPLES: readcolumn x 1 % x data are in column 1 readcolumn y 4 % y data are in column 2 graphlimits % automatic limits plotpoints $$plotpolygon [ Closed [ Baseline ]] Connect the (x, y) points to form a polygon ARGUMENTS: Closed ± if true, connect the end points of the polygon Baseline ± if specified, connect the end points to this baseline DESCRIPTION: Use $b$plotpolygon$b$ to connect the ($i$x$i$, $i$y$i$) points to form a polygon. Asymptote uses the current fillpattern and pen characteristics to draw and fill the polygon. The two optional arguments to $b$plotpolygon$b$ allow you to close the polygon by connecting its end points. If you specify $i$true$i$ for the first argument, $b$plotpolygon$b$ connects the end points of the curve. If you also supply the second argument, the baseline level, Asymptote connects the end points of the polygon to the baseline. This option is useful when you want to fill under a curve with a pattern. For example, setting the baseline to 0.0 shades the integral under a curve. Remember to set $b$cliptoframe$b$ to $i$true$i$ if you donàt want Asymptote to plot any part of the polygon that extends outside the graph frame. SEE ALSO: $b$pencolor$b$ $b$penpattern$b$ $b$fillpattern$b$ $b$pendash$b$ $b$penmode$b$ $b$pensize$b$ $b$readcolumn$b$ $b$readrow$b$ $b$plotline$b$ $b$plotpoints$b$ $b$plothistogram$b$ $b$ploterrors$b$ $b$plotarrows$b$ $b$cliptoframe$b$ EXAMPLES: readcolumn x 1 % x data are in column 1 readcolumn y 2 % y data are in column 2 graphlimits % automatic limits fillpattern black pencolor blue plotpoly plotpoly % connect the x, y points to form a polygon plotpolygon closed % connect the end points to each other penpattern none % turn off the pen fillpattern gray % set to fill with gray plotpoly closed 0.0 % fill under (or up to) y= 0.0 with gray penpattern black % turn the pen back on pensize 4 % make it thick plotpoly open % draw a thick black line for the actual data $$pointsize points Set the point symbol to use when drawing points ARGUMENTS: points ± point size when scale = 1.0 (in points) Use $b$pointsize$b$ to set the size (in points) that you want Asymptote to use for points when the scale factor is set to 1.0. The $b$pointsize$b$ command is a handy way to adjust the size of your point symbols without having to change $b$scale$b$ every time you draw points. The default point size is 6 points. You may want to add the $b$pointsize$b$ command to your Start Up script if you want to change this default. SEE ALSO: $i$graphics environment$i$ $b$pointsymbol$b$ $b$plotpoints$b$ EXAMPLES: pointsize 6 % set the point size to 6 points scale 1 plotpoints % draw points that are 6 points in diameter scale 2 plotpoints % draw 12 pt points $$pointsymbol nsides style Set the point symbol to use when drawing points ARGUMENTS: nsides ± the number of sides for polygon style ± the style open (=0) cross (=1) star (=2) filled (=3) DESCRIPTION: Use $b$pointsymbol$b$ to choose which symbol Asymptote uses to plot points on your graph. To plot the same symbol at each point, first use $b$pointsymbol$b$ to specify the point symbol you want, and then use $b$plotpoints$b$ to plot the points. Point symbols in Asymptote are drawn as regular polygons that are either open (connect the vertices of the polygon), or filled (same as open but fill the polygon with the current fill pattern), drawn as a cross (connect the vertices to the center of the point), or drawn as a star (connect the vertices to a mid-point). To draw different symbols at each point, use the $b$readcolumn$b$ or $b$readrow$b$ commands to read the point symbols from a file, or use $b$rpn$b$ to calculate the symbol to use at each point. See the description of the $b$readrow$b$ and $b$readcolumn$b$ commands for more information about how to read point symbols from a file. You can shrink or enlarge the points with the $b$scale$b$ command or you can change the default point size with $b$pointsize$b$. Change the color of points with $b$pencolor$b$ and their fill patterns with $b$fillpattern$b$. You can also rotate points with $b$rotation$b$ (to draw, for example, diamonds rather than squares). SEE ALSO: $i$graphics environment$i$ $b$pencolor$b$ $b$pensize$b$ $b$penpattern$b$ $b$penmode$b$ $b$fillpattern$b$ $b$scale$b$ $b$rotation$b$ $b$pointsize$b$ $b$readcolumn$b$ $b$readrow$b$ EXAMPLES: pointsymbol 4 filled % set the point symbol to filled squares fillpattern gray pencolor red plotpoints readcolumn x 1 % read x data from column 1 readcolumn y 2 % read first set of y data from column 2 pointsymbol 3 filled % choose filled triangles plotpoints % plot the points readcolumn y 3 % read the second set of y data from column 3 rotation 180 % set the rotation angle to 180 degrees plotpoints % draw the second set of points with upside down triangles $$print Print the current graph ARGUMENTS: none DESCRIPTION: Issue the $b$print$b$ command to print your graph on the printer selected in the Chooser. The Chooser is located in the $i$Apple$i$ menu. You can put the $b$print$b$ command in a script to generate plots and print them automatically. This feature even works in the background under MultiFinder or System 7 so you can send your graphs to the printer while you do other work. To fully automate your printing, you can also save the page setup in your script. Your script can then specify the page setup with the $b$pagesetup$b$ command. See the description of $b$pagesetup$b$ for more information. SEE ALSO: $b$pagesetup$b$ $b$run$b$ EXAMPLES: pagesetup ? % Ask for the pagesetup readcolumn x 1 % Read the data... readcolumn y 2 graphlimits drawframe plotline % ... and plot a line print % Print the graph pagesetup % Read a previously saved page setup from this script readcol x 1 readcol y 2 graphlimits drawframe plotpoints print % Print the graph $$publish Publish the current graph ARGUMENTS: none DESCRIPTION: Use $b$publish$b$ to publish the current contents of the $i$Graph Window$i$ in a PICT format edition file. If you havenàt saved the $i$Graph Window$i$ to a publication, Asymptote displays the Edit>Create˚Publisher dialog box where you can name the new publication. If the $i$Graph Window$i$ already is a publisher, the publish command updates the publisher with the current contents of the $i$Graph Window$i$. This has the same effect as selecting Edit>Publisher˚Options and then clicking the Publish Now button. For a detailed description Asymptoteàs Publish and Subscribe features, see Appendix E of the Asymptote $i$User's Guide$i$. SEE ALSO: $b$print$b$ EXAMPLE: publish $$quit Quit Asymptote and return to the Finder ARGUMENTS: none DESCRIPTION: Use $b$quit$b$ just as you would use File>Quit. When you quit, Asymptote checks to see if you have saved changes you made to text files. If you havenàt, Asymptote asks you if you want to save the changes before quitting. You can put the $b$quit$b$ command at the end of a script to have Asymptote quit automatically when it reaches the end of the script. EXAMPLE: readcolumn x 1 readcolumn y 2 graphlimits drawframe plotline print % send the plot to the printer clear % erase the graph so Asymptote won't ask if you want to save it quit % quit and return to the Finder $$readcolumn vectorName n Read a column of numbers into one of Asymptoteàs vectors ARGUMENTS: vectorName ± the name of the vector ($i$x$i$, $i$y$i$, $i$e$i$, $i$p$i$, or $i$l$i$) to store the data n ± the column number to read from the data file DESCRIPTION: Use $b$readcolumn$b$ to read a column of numbers or labels from your data file into one of Asymptoteàs vectors. Before you read the data, you must first specify which data file to use with $b$datafile$b$. If you want, you can use $b$datalines$b$ to specify which lines you want to read. If the columns of numbers in your data file are not separated by spaces, commas or tabs, you may want to use $b$datacolumns$b$ to specify how to read the $i$y$i$ data. See the description of $b$datacolumns$b$ for more information about this feature. READING NUMBERS FROM A DATA FILE: To read numbers from your data file into one of Asymptoteàs vectors, simply type the name of the vector and number of the column you want to read following the $b$readcolumn$b$ command. If you donàt know the number of the column you want, click the column and select Data>Read˚Data>From˚Column. Asymptote displays a dialog box and enters the number of the column you selected. READING LABELS FROM A DATA FILE: With Asymptote you can read text labels for your points and plot a different label for each point on your graph. First, read the coordinates of the points with readcolumn x and readcolumn y, then read the point labels with readcolumn l. If your labels include spaces, commas or tabs, you must enclose them in quotes. Use two quotes ("") if you need to insert a quote in a label. In the following example, a portion of the data file looks like this: 1.1 21 Fred 34.3 1.2 22 Hi! 343.0 1.3 23 "1,2,3" 343.0 1.4 24 "How are you?" 29.2 1.5 25 ""OK,"" he said." 19.2 As with all Asymptote data files, you don't need to align the columns of the data file as they appear in this example. Just be sure that each row contains enough entries and that each entry is separated with spaces, a comma or a tab. You could read the points and their labels with the following commands: readcolumn x 1 readcolumn y 2 graphlimits % show all of the points plotpoints % plot 'em % select a font for the labels: font Helvetica readcolumn l 3 % read the labels plotlabels aboveleft % plot the labels The above example plots the points using the current $b$pointsymbol$b$, and places the labels above and to the left of each point. It uses $b$fontname$b$ to select the font for the labels before plotting them with $b$plotlabels$b$. You could insert a $b$scale$b$ command before calling $b$plotlabels$b$ to adjust the size of the labels or a $b$rotation$b$ command to rotate them about each point. READING POINT SYMBOLS FROM A DATA FILE: You can use $b$readcolumn$b$ to read point symbols from your data file in order to plot a different symbol at each point. The number of sides and the style of each point in the $i$p$i$ vector must be combined into a single number as follows: Tens and Hundreds digits: number of sides for the point Ones digit: point style (open, cross, star, filled) Fractional part: scale factor Sign: if negative, rotate by (180/number of sides)¡ For example, a value of -43.5 in the $i$p$i$ vector produces a filled square, 0.5 times smaller than the current scale factor which is rotated by 45¡. If a value in the $i$p$i$ vector for a particular point is zero, Asymptote wonàt plot it. You can use this feature to select the points to plot based on some information in your data file. For example, to plot all points which have a value in the $i$e$i$ vector greater than 100, you could use the following commands: rpn <e 100 > % leave 1's and 0's on the stack if e > 100 rpn p % zero all the p vector elements with e < 100 You can also use $b$rpn$b$ to calculate the point symbols for the $i$p$i$ vector. For example, suppose your data file contains the following information about some automobiles: Column Value 1 miles per gallon 2 weight 3 4, 6, or 8 cylinders 4 horse power To plot miles per gallon $i$vs.$i$ weight, using filled triangles, squares and circles for 4, 6, or 8 cylinders respectively, you could use these commands: readcolumn x 1 % read the x values readcolumn y 2 % read the y values readcolumn p 3 % read the p values (= 4,6 or 8) rpn <p 8 = 15 * % replace all 8's with 15 (for circles) rpn p % make the point filled (33,43,153) To plot only the automobiles that have a horse power greater than 100 add the following commands before plotting the points with $b$plotpoints$b$: rpn % if horse power > 100, leave 1 on stack, else 0 rpn * >p % multiply the previously saved points symbols and % store the new point symbols in the $i$p$i$ vector Note that this example uses the calculator stack to temporarily hold the point symbols in order to read the horse power data in to the $i$p$i$ vector. Alternatively you could scale the size of each point based on the horse power of the car with the following commands: rpn p % add the fractional part to the original p vector % which was saved on the stack Finally, you could rotate all of the points which had a horse power of 120 or greater with the following commands: rpn % put 1 on the stack if horse power > 120, else 0 rpn -2 * 1 + % now, -1 if horse power >120, 1 if not rpn * >p % make all horse power >120 p vector values negative SEE ALSO: $b$readrow$b$ $b$datafile$b$ $b$datalines$b$ $b$datacolumns$b$ EXAMPLE: datafile 1990 data % Open the data file "1990 data" datalines 10 100 % use only lines 10 through 100 readcolumn y 3 % read these values from column 3 of the file into y $$readcursor [ delay ] Use the graph cursor to read values into the x and y vectors ARGUMENTS: delay ± 1/60th of a second to delay between reading points when the mouse button is held down (0 = read a single point with each click) DESCRIPTION: With $b$readcursor$b$ you can read points from your graph using the graph cursor and store the values in the $i$x$i$ and $i$y$i$ vectors. When you issue the $b$readcursor$b$ command, Asymptote activates the graph cursor. If you specify a delay following the $b$readcursor$b$ command, Asymptote begins reading a stream of values from your graph as soon as you press and hold down the mouse button. The delay argument controls how many 1/60ths of a second to wait between reading points in the stream. If you don't specify a delay (or you give 0 for the delay) Asymptote reads only one point with every click of the mouse. To stop reading points, hold down the command and period keys or click outside the $i$Graph Window$i$. SEE ALSO: $b$export$b$ EXAMPLE: showgraph readcursor plotpoints $$readrow vectorName n Read a row into one of Asymptoteàs vectors ARGUMENTS: vectorName ± the name of the vector ($i$x$i$, $i$y$i$, $i$e$i$, $i$p$i$, or $i$l$i$) to store the data n ± the row number to read from the data file DESCRIPTION: Use $b$readrow$b$ to read a row of numbers from your data file into one of Asymptoteàs vectors. Before you read the data, you must first specify which data file to use with $b$datafile$b$. If you donàt want to read all of the values in a row, use $b$datacolumns$b$ to specify which columns you want. READING NUMBERS FROM A DATA FILE: To read numbers from your data file into one of Asymptoteàs vectors, simply type the name of the vector and number of the row you want to read following the $b$readrow$b$ command. If you donàt know the number of the row you want, click the row then select Data>Read˚Data>From˚Row. Asymptote displays a dialog box and enters the number of the row you selected. READING LABELS FROM A DATA FILE: With Asymptote you can read text labels for your points and plot a different label for each point on your graph. First, read the coordinates of the points with readrow x and readrow y, then read the point labels with readrow l. If your labels include spaces, commas or tabs, you must enclose them in quotes. Use a two quotes ("") if you need to insert a quote in a label. For example, assume that your data file looks like this: Fred Hi! "1,2,3" "How are you?" ""OK,"" he said."" 1.1 1.2 1.3 1.4 1.5 21 22 23 24 25 As with all Asymptote data files, the columns of the file don't need to be aligned as they are in this example. Just be sure that each row contains the required number of items and that each entry is separated by spaces, a comma or a tab. To plot the points and their labels from this data file use the following commands: readrow x 1 readrow y 2 graphlimits % show all the points plotpoints font Helvetica readrow l 3 plotlabels aboveleft This example plots the points using the current $b$pointsymbol$b$, and places the labels above and to the left of each point. It uses $b$fontname$b$ to select the font for the labels before plotting them with $b$plotlabels$b$. You could insert a $b$scale$b$ command before using $b$plotlabels$b$ to adjust the size of the labels or a $b$rotation$b$ command to rotate them about each point. READING POINT SYMBOLS FROM A DATA FILE: You can use $b$readrow$b$ to read point symbols from your data file in order to plot a different symbol at each point. The number of sides and the style of each point in the $i$p$i$ vector must be combined into a single number as follows: Tens and Hundreds digits: number of sides for the point Ones digit: point style (open, cross, star, filled) Fractional part scale factor Sign if negative, rotate by (180/number of sides)¡ For example, a value of -43.5 in the $i$p$i$ vector produces a filled square, 0.5 times smaller than the current scale factor which is rotated by 45¡. If a value in the $i$p$i$ vector for a particular point is zero, Asymptote wonàt plot it. You can use this to select the points to plot based on some information in your data file. For example, to plot all points which have a value in the $i$e$i$ vector greater than 100, you could use the following commands: rpn <e 100 > % leave 1's and 0's on the stack rpn p % zero all the p vector elements with e < 100 You can also use $b$rpn$b$ to calculate the point symbols in the $i$p$i$ vector. For example, suppose your data file contains the following information about some automobiles: Row Value 1 miles per gallon (MPG) 2 weight 3 4, 6, or 8 cylinders 4 horse power To plot lot MPG $i$vs.$i$ weight, using filled triangles, squares and circles for 4, 6 or 8 cylinders, you could use the following commands: readrow x 1 % read the x values readrow y 2 % read the y values readrow p 3 % read the p values(4,6 or 8) rpn <p 8 = 15 * % replace all 8's with 15 (for circles) rpn p % add 3 to make them filled (33,43,153) To plot only the automobiles that had a horse power greater than 100 add the following commands before plotting the points with $b$plotpoints$b$: rpn % if horse power>100, leave 1 on stack, else 0 rpn * >p % multiply the previously saved point symbols % and store the new point symbols Notice that this example uses the calculator stack to temporarily hold the point symbols in order to read the horse power data in to the $i$p$i$ vector. Alternatively, you could scale the size of each point based on the horse power of the car with the following commands: rpn p % add the fractional part to the original % $i$p$i$ vector which was saved on the stack Finally, you could rotate all of the points which had a horse power of 120 or greater with the commands: rpn % put 1 on the stack if horse power>120,else 0 rpn -2 * 1 + % now, -1 if horse power >120, 1 if not rpn * >p % make the p vector values negative if horse power > 120 SEE ALSO: $b$readcolumn$b$ $b$datafile$b$ $b$datalines$b$ $b$datacolumns$b$ EXAMPLE: datafile 1990 data % Open the data file "1990 data" datacolumns 2 11 % skip the first item and read the next 10 items readrow x 3 % read these values from column 3 of the file into x $$repeat expression times command Repeat a command (or run a script) several times ARGUMENTS: expression ± an expression for the number of times to repeat the command or script command ± the command or script to repeat DESCRIPTION: Use $b$repeat$b$ to execute a script or a command a specified number of times. Following the $b$repeat$b$ command you must provide an expression that evaluates to a single number. This expression is the number of times to repeat the command or script. After the expression, type the word 'times' followed by the command or script you want to run. SEE ALSO: $b$while$b$ $b$if$b$ EXAMPLES: repeat 5 times myscript % execute the script ¾myscriptà 5 times set nloops npts 2 / % nloops = half the number of points repeat nloops scaledata 2 3 npts % run the script 'scaledata' nloops times % with 2, 3 and npts as arguments to 'scaledata' repeat npts 2 / scaledata 2 3 npts % Same as the above rpn 1 % put the constant vector 1 on the stack repeat 5 times rpn 2 * % calculate the powers of 2 from 1 to 5 repeat npts 1 - times myscript % repeat 'myscript' npts - 1 times $$return Stop the current script and return to the script that ran the current script ARGUMENTS: none DESCRIPTION: Use $b$return$b$ in a script when you want to stop executing the current script and return to the script that ran the current script (if any). For example, you might return from a script if a certain condition is met as in the following example: set NumLeftToDo NumLeftToDo 1 - if NumLeftToDo 0 <= then return In this example, Asymptote returns from the script if the variable NumLeftToDo is 0 or less. When this happens, the commands following the $b$if$b$ test are not run. Note: The $b$return$b$ command can only be executed from a script. You can't execute $b$return$b$ from the $i$Command Window$i$. SEE ALSO: $b$stop$b$ $b$pause$b$ $b$quit$b$ EXAMPLES: ask Continue Yes No ?Do you want to process another data set? if Continue false = then return if beta 34 * < alpha then return else calculate_next_alpha $$rotation degrees Set the rotation angle for labels and points ARGUMENTS: degrees ± the angle in degrees, counter clock wise from x axis DESCRIPTION: Use $b$rotation$b$ to specify how Asymptote should rotate labels and points. The rotation angle you supply is measured in degrees, counter-clockwise from the $i$x$i$ (horizontal) axis. A rotation angle of 0¡ points to the right. A rotation of 90¡ points up the page. SEE ALSO: $b$drawlabel$b$ $b$plotlabels$b$ $b$plotpoints$b$ $b$pointsymbol$b$ EXAMPLES: readcolumn x 1 readcolumn y 2 % read the first set of y points pointsymbol 3 filled % filled triangles for points plotpoints readcolumn y 3 % read some other data rotation 180 plotpoints % draw the triangles upside down graphlimits 0 1 0 1 moveto .5 .5 rotation 45 drawlabel right This is a rotated label $$rpn expression Use the vector calculator to calculate a reverse polish notation (RPN) expression ARGUMENTS: expression ± a RPN expression (see below) DESCRIPTION: Use $b$rpn$b$ to access Asymptote's powerful vector calculator. You might use $b$rpn$b$ to calculate a formula, to manipulate the data before plotting, or to calculate point symbols for use by the $b$plotpoints$b$ command. If you are not familiar with reverse polish notation, read Appendix D. The easiest way to write an $b$rpn$b$ expression is to use the $i$Calculator˚Window$i$. As you perform calculations in the $i$Calculator Window$i$, Asymptote writes the appropriate $b$rpn$b$ expressions for you. You can use the $i$Vectors˚Window$i$ to examine the calculator stack and the values in Asymptote's vectors. To enter a constant in an expression, simply type its value and press the Enter key. Asymptote $i$pushes$i$ the value on the bottom of the calculator stack. The other vectors on the stack are pushed up. When $b$rpn$b$ encounters a binary operator (operators such as +,-,/,*), it $i$pops$i$ two values off the bottom of the stack, performs a calculation and pushes the result on the bottom of the stack. For unary operators (for example rms, sqrt or sin), $b$rpn$b$ replaces the bottom vector of the stack with the results of the calculation. The calculator stack has a depth of at least 4 (that means it can remember the last 4 vectors you pushed). You can use File>Options>Memory˚Use to add more vectors to the calculator stack or allocate more registers to use in your calculations. The following table lists all of the $b$rpn$b$ operators and functions: $b$RPN CALCULATOR OPERATORS$b$ stack x = bottom vector on the stack (not the x vector) stack y = 2nd to the bottom vector on the stack (not the y vector) In the $i$Vectors Window$i$ the vectors on the stack are numbered 0 through 3. The vector labeled ¾Stack 0à is stack x, the vector labeled ¾Stack 1à is the same as y). ___ $i$Store/Recall Operators$i$ _____________________________________________ The following operators push an Asymptote vector onto the bottom of the stack: <x push the $i$x$i$ vector onto the bottom of the stack (stack x) <y push the $i$y$i$ vector onto the bottom of the stack (stack x) <p push the $i$p$i$ vector onto the bottom of the stack (stack x) <e push the $i$e$i$ vector onto the bottom of the stack (stack x) <rn push the register n onto the bottom of the stack (stack x) The following commands copy stack $i$x$i$ into one of Asymptoteàs vectors. They do not alter the calculator stack: >x store stack $i$x$i$ in the $i$x$i$ vector >y store stack $i$x$i$ in the $i$y$i$ vector >p store stack $i$x$i$ in the $i$p$i$ vector >e store stack $i$x$i$ in the $i$e$i$ vector >rn store stack $i$x$i$ in register n ___ $i$Stack Operators$i$ __________________________________________________ The following operators manipulate the stack: dup duplicate stack $i$x$i$ drop pop stack $i$x$i$ off the stack and drop the stack down xy swap stack $i$x$i$ and stack $i$y$i$ cx clear stack $i$x$i$ (replace stack $i$x$i$ with zeros) rad switch to radians for subsequent calculations deg switch to degrees for subsequent calculations ___ $i$Logical Operators$i$ _______________________________________________________ The following operators pop two vectors off the stack, compare them with a logical test, and push the results of the test with a vector of 1às and 0às (true or false). = push 1 if x = y, else 0 <> or › push 1 if x › y, else 0 < push 1 if x < y, else 0 > push 1 if x > y, else 0 <= push 1 if x <= y, else 0 >= push 1 if x >= y, else 0 ___ $i$Unary Operators$i$ _____________________________________________________________ The following operators pop stack x, calculate something with it, and push the result on the stack: ! replace stack $i$x$i$ with its factorial chs replace stack $i$x$i$ with -$i$x$i$ int replace stack $i$x$i$ with integer portion of $i$x$i$ frac replace stack $i$x$i$ with fractional portion of $i$x$i$ abs replace stack $i$x$i$ with absolute value of $i$x$i$ sqrt replace stack $i$x$i$ with square root of $i$x$i$ sin replace stack $i$x$i$ with sine of $i$x$i$ (units set by rad/deg) cos replace stack $i$x$i$ with cosine of $i$x$i$ (units set by rad/deg) tan replace stack $i$x$i$ with tangent of $i$x$i$ (units set by rad/deg) asin replace stack $i$x$i$ with arcsine of $i$x$i$ (units set by rad/deg) acos replace stack $i$x$i$ with arccosine of $i$x$i$ (units set by rad/deg) atan replace stack $i$x$i$ with arctan of $i$x$i$ (units set by rad/deg) log replace stack $i$x$i$ with log (base 10) of $i$x$i$ ln replace stack $i$x$i$ with log (base e) of $i$x$i$ 10^x replace stack $i$x$i$ with 10 raised to the $i$x$i$ power e^x replace stack $i$x$i$ with e raised to the $i$x$i$ power hrs convert hhmmss.s notation to decimal hours hms convert decimal hours to hhmmss.s notation index replace stack $i$x$i$ with 1,2,3,4,5...n ran replace stack $i$x$i$ with a random number (-1,1) max replace stack $i$x$i$ with the maximum of $i$x$i$ min replace stack $i$x$i$ with the minimum of $i$x$i$ mean replace stack $i$x$i$ with the mean of the $i$x$i$ vector sum replace stack $i$x$i$ with the sum of the $i$x$i$ vector rms replace stack $i$x$i$ with the root mean square of the $i$x$i$ vector ___ $i$Binary Operators$i$ _______________________________________________________ The following operators pop stack $i$x$i$ and stack $i$y$i$ stack, calculate something and push the results of a calculation: + push y + x - push y - x / push y / x * push y * x y^x push y raised to the x power ________________________________________________________________________________ You must separate operators and values in an $b$rpn$b$ expression with spaces. For example donàt use: rpn <x56 <y* use rpn <x 56 + <y * instead. If you need to calculate something using several different columns of your data file, remember that you can store intermediate results of your calculator on the calculator stack, in registers or any of the $i$x$i$, $i$y$i$, $i$e$i$ and $i$p$i$ vectors. In this way you can read some data, perform some calculations in $b$rpn$b$ leaving the results on the stack, read some more data and then finish the calculation. For example, to store the sum of columns 1 through 3 of your data file divided by column 7, you could use the following commands: readcol x 1 readcol y 2 readcol e 3 rpn <x <y <e + + % push all three vectors and add together readcol e 7 % read some more data into the e vector rpn <e / % divide the sum by the data in the e vector rpn >x % store the result in the x vector $$run [ scriptname ] Run the Recorder or some other script ARGUMENTS: scriptname ± the name of the script to run DESCRIPTION: Use $b$run$b$ to run script. If you donàt specify the name of the script, Asymptote runs the Recorder. If you specify the script to run, Asymptote searches for it automatically using the current $i$search paths$i$ file. You might create a directory with your favorite scripts and then add the path to that directory to your Search Paths file. Then, whenever you type the name of one of your scripts in the $i$Command Window$i$ or in a script, Asymptote opens and runs the script automatically. Remember, it is not necessary to use $b$run$b$ to run a script. Most scripts can be run by simply typing the script name as if it were an Asymptote command. In other words, the command run MyScript is the same as the command MyScript When Asymptote encounters a command thatàs not an Asymptote command, it assumes the command is the name of a script. Asymptote tries to locate a file with that name and run it. If there are spaces in the script name, however, you canàt type the script name as a command and must use the $b$run$b$ command instead. For example, you could run the script ¼Plot January Data½ with the command run Plot January Data but just typing Plot January Data produces an error because Asymptote tries to locate a script named ¼Plot½ and assumes that ¼January½ and ¼Data½ are the arguments to the command ¼Plot.½ Note that you could avoid this problem by naming the file ¼Plot_January_Data½ instead. PASSING ARGUMENTS TO SCRIPTS: You can pass arguments to a script by specifying the arguments after the script name. Use &n, where n is a number to denote the value of the nth argument. For example, if the script 'scaledata' contained the following commands: rpn <x &1 * >x rpn <y &2 * >y and you typed scaledata 2.3 34.9 in the $i$Command Window$i$, Asymptote multiplies the $i$x$i$ vector by 2.3 and the $i$y$i$ vector by 34.9. You can also pass labels as arguments to scripts. If they include spaces, enclose them in quotes like this: addmylabels "March 12 run" "New atomic constants" You can also pass expressions as arguments to scripts if you also include them in quotes as in this example: scaledata "\npts 10 *" 34.9 The first argument to the script 'scaledata' is the expression "\npts 10 *" (10 times the current number of points) and the value of the second argument is 34.9. When 'scaledata' runs, it scales the $i$x$i$ data by 10 times the number of points and the $i$y$i$ data by the constant 34.9. USING THE SEARCH PATHS FILE TO OPEN YOUR SCRIPT FILE AUTOMATICALLY: If Asymptote canàt locate a script for you automatically, make sure you have properly specified a search path to the file in the current paths file and that youàve spelled the name of the file correctly (including spaces). For help using the Search Paths file, see Appendix B of the $i$User's Guide$i$ or type help Search Paths in the $i$Command Window$i$. SPECIFYING THE FULL OR PARTIAL PATH NAME OF YOUR FILE: Itàs best to let Asymptote locate a file for you automatically by putting a path to the file in your Search Paths file. If you want to open a specific file in a specific directory, you can specify the full or partial path name of the file when you issue the $b$run$b$ command. Full path names start with a disk name (usually your hard disk name) and are followed by the name of each subfolder separated by colons and end with the name of the file. For example, to run the script "loaddata" in the folder "March 12" which is on the hard disk named "My Disk" you could use the following command: run My disk:March 12:loaddata Alternatively, if the folder "March 12" were in the same folder with Asymptote, you could use the partial path name: run :March 12:loaddata to run the script. Note that partial path names begin with a colon, while full path names do not. Partial path names always start their search starting with the folder that contains Asymptote. SEE ALSO: $i$search paths$i$ $b$pause$b$ $b$stop$b$ $b$quit$b$ EXAMPLES: % The following commands are three different ways to run the same script assuming % that the path % HardDisk:New Data:* % is in the current search path run myscript myscript HardDisk:New Data:myscript $$savegraph Save the current graph to a PICT file ARGUMENTS: none DESCRIPTION: The $b$savegraph$b$ command is the same as selecting File>Save Graph. SEE ALSO: $b$publish$b$ $$scale factor Set the scale factor for labels, points and tickmarks ARGUMENTS: factor ± the scale factor DESCRIPTION: The $b$scale$b$ parameter of the $i$graphics environment$i$ controls the sizes of labels, points and the length of tickmarks and error bar caps. A scale factor of 1.0 draws points, labels and tick marks at their default size. You can change these defaults using $b$pointsize$b$ $b$fontsize$b$ and $b$ticksize$b$. If you donàt change the defaults, Asymptote uses 12 points for text and tick marks and 6 points for point symbols. With these defaults, if you set $b$scale$b$ to 2, Asymptote draws 24 point text and tick marks and 12 point symbols. SEE ALSO: $i$graphics environment$i$ $b$rotation$b$ $b$drawframe$b$ $b$drawlabel$b$ $b$drawxlabel$b$ $b$drawylabel$b$ $b$drawtitle$b$ $b$plotpoints$b$ $b$drawpoint$b$ $b$fontsize$b$ $b$ticksize$b$ $b$pointsize$b$ EXAMPLES: scale 2.0 drawlabel centerleft This label is twice as big scale 1 drawtitle This is a 12˚pt title scale 1.2 moveto .5 .5 pointsymbol 5 star drawpoint scale scale 2 * % make the scale twice as big moveto .5 .5 drawpoint readcolumn x 1 readcolumn y 2 graphlimits scale .75 drawframe % draw a frame with reduced tickmarks pointsymbol 4 cross scale 1.0 plotpoints % draw normalized points readcolumn y 3 % read some more y data scale 2.0 plotpoints % draw these points twice as big $$set variablename expression Set the value of a variable ARGUMENTS: variablename ± the name of the variable to set expression ± an expression for the value to set DESCRIPTION: Use the $b$set$b$ command to alter the value of a variable. If the variable doesnàt exist, Asymptote creates a new one and sets its initial value. If you want to have the script ask the user (a technician, perhaps) to set the value of a user variable while it is running, replace the expression with a question mark followed by a prompt. The prompt is optional, so if you donàt supply one Asymptote supplies a prompt. For example, the command set myvar ?What should be the value for myvar? displays a dialog box that asks you to specify ¾myvar.à When Asymptote displays the dialog box, it uses the current value of the variable as the default expression. Thus, to change the default response simply set the variable first, then use $b$set$b$ again to ask for a new value. For example, the following commands set myvar 28.9 set myvar ?What should be the value for myvar? ask you to set myvar after setting the default response to 28.9. If you use $b$set$b$ with a question mark prompt to define a variable that doesnàt exist, Asymptote displays an message asking if you want to create a new variable. This feature helps you avoid confusion due to misspelled variable names. To prevent Asymptote from asking if you want to create the variable, simply set the variable to some default value first, and then use the $b$set$b$ command with a question mark. SEE ALSO: $i$Variables and Constants$i$ $b$rpn$b$ EXAMPLES: set myvar x(10) 23 + % set 'myvar' to be x(10) plus 23 set xyz npts 1 - % set 'xyzà = current number of points minus 1 set count count 1 + % increment 'count' by 1 set NumToDo 5 % Make 5 the default number of items to do set NumToDo ?How many items do you want to process? repeat NumToDo times process_another_item $$showgraph Zoom the $i$Graph Window$i$ to show the graph frame ARGUMENTS: none DESCRIPTION: The $b$showgraph$b$ command is the same as selecting Plot>Show˚Graph. Asymptote centers the frame in the $i$Graph Window$i$ by scrolling and zooming your graph. You can use $b$showgraph$b$ in a script to display the graph in the $i$Graph Window$i$. SEE ALSO: $b$showpage$b$ fullscreen $$showpage Zoom the $i$Graph Window$i$ to show the entire page ARGUMENTS: none DESCRIPTION: The $b$showpage$b$ command is the same as selecting Plot>Show˚Graph. Asymptote centers the page in the $i$Graph Window$i$ by scrolling and zooming your graph. You can use $b$showpage$b$ in a script to display the entire page in the $i$Graph Window$i$. SEE ALSO: $b$showgraph$b$ fullscreen $$showwindow [ windowName ] Make a window visible ARGUMENTS: windowName ± the name of the window to show DESCRIPTION: Use $b$showwindow$b$ to make a window visible after it was hidden with $b$hidewindow$b$. If you don't specify a window name, Asymptote makes the current window visible. You can use the command showwindow \f or showwindow \r to show the current data file and Recorder windows . EXAMPLES: showwindow test data % make the window 'test data' visible showwindow \f % Show the current data file window, whatever its name is hidewindow % hide this window ask junk "I, know" "Who cares?" ¼You can't see me!½ showwindow % make this window visible again $$smooth width Smooth the y vector with a variable width window ARGUMENTS: width ± the width of the smoothing window DESCRIPTION: When you use $b$smooth$b$, Asymptote takes the Fast Fourier Transform (FFT) of the $i$y$i$ vector, smoothes it by a window with the width you specify (roughly the number of points to average), takes the inverse FFT and replaces the $i$y$i$ vector with the smoothed data. Another way to smooth your data is with the $b$spline$b$ command. EXAMPLES: readcolumn x 1 readcolumn y 2 graphlimits plotpoints % plot the unsmoothed data smooth 2.3 plotline % plot a smoothed line $$sort Sort the y, e, p and l vectors by increasing x ARGUMENTS: none DESCRIPTION: When you issue the $b$sort$b$ command, Asymptote sorts the $i$y$i$, $i$e$i$, $i$p$i$, and $i$l$i$ vectors by ascending value of the $i$x$i$ vector. The calculator stack and its registers are unchanged. You can use $b$sort$b$ to sort the $i$x$i$ and $i$y$i$ points so they can be connected with a line that goes smoothly from left to right. In addition, some commands, like $b$spline$b$, only work on sorted data so you must use $b$sort$b$ before you can use them. EXAMPLES: readcolumn x 1 readcolumn y 2 sort plotline $$spline [ npts ] Calculate the natural cubic spline of y= f(x) ARGUMENTS: npts ± the number of points in the splined curve DESCRIPTION: Use $b$spline$b$ to calculate the natural cubic spline of the curve $i$y$i$ = f($i$x$i$). Asymptote replaces the $i$x$i$ and $i$y$i$ vectors with the calculated spline curve. You can specify, npts, the number of points in the spline. If you don't supply npts, $b$spline$b$ uses four times the current number of points for the spline curve. Asymptote distributes the points evenly from $i$xleft$i$ to $i$xright$i$. If the values in the $i$x$i$ vector are not in order, you must sort them first with the $b$sort$b$ command before using $b$sort$b$. EXAMPLES: readcolumn x 1 readcolumn y 2 sort graphlimits % do this to set \xleft and \xright using the x vector data plotpoints spline 100 % calculate a spline of 100 points plotline % and plot it on top of the points graphlimits 10 12.3 0 spline 25 % calculate a spline of 25 points running from x= 10 to 12.3 $$stop Stop running the current script ARGUMENTS: none DESCRIPTION: Putting $b$stop$b$ in a script stops running the script. The $b$stop$b$ command is the same as selecting Script>Stop. But if you want to stop running a script $i$and$i$ quit Asymptote too, use $b$stop$b$. SEE ALSO: $b$quit$b$ $b$pause$b$ $b$return$b$ EXAMPLE: ask AllDone Yes No Do you want to stop running this script? $$textmode [ n ] Set the transfer mode for drawing text ARGUMENTS: n ± a mode number or ± a mode name(opaque, transparent, reversed) DESCRIPTION: Use $b$textmode$b$ to select a text drawing mode. Some constants have been defined to help you choose a mode, they are $i$opaque$i$, $i$transparent$i$, and $i$reversed$i$. To choose a mode graphically type: textmode ? to see an illustration. Keep in minds that most PostScript printers, including the LaserWriter, do not make use of text transfer modes. This is a feature of the LaserWriter driver supplied by Apple. Text modes are visible on QuickDraw based printers, however. SEE ALSO: $i$Variables and Constants$i$ $b$fontname$b$ $b$scale$b$ $b$penmode$b$ $b$pencolor$b$ $b$pensize$b$ $b$pendash$b$ $b$penpattern$b$ EXAMPLES: moveto .5 .5 fillpattern black pencolor black pointsymbol 4 filled scale 5 drawpoint % draw a big black square scale 1.0 moveto .5 .5 textmode reversed drawlabel center This label is reversed $$ticksize points Set the default tick mark size ARGUMENTS: points ± tick mark size when scale = 1.0 (in points) DESCRIPTION: Use $b$ticksize$b$ to set the size (in points) that you want Asymptote to use tick marks when the scale factor is set to 1.0. The $b$ticksize$b$ command is a handy way to adjust the size of tickmarks without having to change $b$scale$b$ every time you draw axes. The default tick mark size is 12 points. You may want to add the $b$ticksize$b$ command to your Start Up script if you want to change this default. SEE ALSO: $i$graphics environment$i$ $b$drawframe$b$ $b$drawaxis$b$ EXAMPLES: ticksize 10 % set the tick size to 10 points scale 1 drawframe % draw 10 point tickmarks scale 2 plotpoints % draw 20 pt tick marks $$while expression do command Execute a command or macro while an expression is true ARGUMENTS: expression ± a logical expression that evaluates to a true (1) or false (0) value command ± a command to execute while the expression remains true DESCRIPTION: Use $b$while$b$ to execute a command while a logical test is true. If the command is the name of a script, Asymptote executes script until the condition is false. Following the $b$while$b$ command you must supply the expression to evaluate, the word $i$do$i$ and the command you want Asymptote to execute. SEE ALSO: $b$repeat$b$ $b$if$b$ EXAMPLES: while notfinished do mymacro % run 'mymacro' until \notfinished is false while x(1) 10 > do rpn <x 2 / >x % keep dividing x by 2 until x(1) is < 100 $$zoomgraph [ factor ] Zoom the graph to display it either reduced or enlarged ARGUMENTS: factor ± the new graph zoom factor (>= 0) > 1 => zoom the graph to show it enlarged =1 => has no effect (ignored) < 1 => zoom the graph to show it reduced = 0 => same as clicking on the zoom box of the $i$Graph Window$i$ DESCRIPTION: Use $b$zoomgraph$b$ to display the graph at a different scale or to zoom the Graph Window to fill the entire screen. Since $b$zoomgraph$b$ shrinks or expands the graph at the point in the center of the $i$Graph Window$i$, you may want to use $b$showgraph$b$ to center your graph first. Clicking the center of your graph with the magnify or demagnify cursors is exactly the same as the $b$zoomgraph$b$ command. With $b$zoomgraph$b$, however, you can specify exactly how much you want to expand or contract the graph. Remember that $b$zoomgraph$b$ does not change the scale of your graph or any of the variables of the $i$graphics environment$i$; it simply changes how the graph is displayed in the $i$Graph Window$i$. SEE ALSO: $b$showgraph$b$ $b$showpage$b$ $b$fullscreen$b$ EXAMPLES: showgraph % center the current graph frame in the $i$Graph Window$i$ zoomgraph 2.5 % expand the graph to display it at % 2.5 times the current size zoomgraph % zoom the $i$Graph Window$i$ to fill the screen showpage % show the entire page in the window $$Reading data Using Asymptote Asymptote data files are ordinary 'TEXT' (ASCII) files. Unlike other Macintosh plotting programs, Asymptote does not 'import' your data into an internal file format that is unreadable by any other program. You donàt have to ¾importà your data every time your data file has changed. With Asymptote, you can be sure that what youàre plotting is up-to-date information. PUBLISH AND SUBSCRIBE: If you are using System 7, you can also use Publish and Subscribe to exchange data between Asymptote and other applications. With Publish and Subscribe, the changes you make to a document in one application are automatically updated in all other applications that ¾subscribeà to the data. For more information on how to use Publish and Subscribe with Asymptote, see Appendix˚E of the $i$Users Guide$i$. READING DATA: To read your data into Asymptote, first specify the file you want to read with the $b$datafile$b$ command. If you want to skip over a header at the top of your data file, or if you want to read only from certain lines or columns of the data file, issue the $b$datalines$b$ or $b$datacolumns$b$ commands. Finally, read the data from columns using $b$readcolumn$b$ or from rows using $b$readrow$b$. These commands store the values or labels you read in one of Asymptote's x, y, e, p or l vectors. Here is an example: datafile MyDataFile % Open the file "MyDataFile" datalines 3 % Skip the first two lines which are a header readcolumn x 1 % Read the values in column 1 into the x vector readcolumn y 3 % Read the values in column 3 into the y vector graphlimits % Find the limits of x and y drawframe % Draw a frame plotpoints % Plot the points FLEXIBLE FILE FORMAT: Asymptote looks for any number of spaces, a tab or a comma to distinguish items in a particular line of your data file. For example, the lines below have 6 columns each: 123 18.9 1E4.4 "Lot A" 0.0000234 99 124 19 1E4.5 "Lot A" 0.0000274 99 125 8 1E4.6 "Lot B" 0.0000232 99 126 23.4 1E4.3 "Lot B" 0.0000172 99 127 0 1E4.1 "Lot B" 0.0000984 99 The columns could be separated by any number of spaces, tabs or a single comma. It's not necessary for the columns of your data file to be lined up in order to read the data into Asymptote. If the columns of your file are not separated this way, you can use $b$datacolumns$b$ to specify which characters to read from each line $i$before$i$ you read any data (see $b$datacolumns$b$ for more information). You can also use Asymptoteàs $i$Search$i$ and $i$Replace$i$ menus to reformat the text as necessary. To do a fancier search and replace, you can use the $i$GREP$i$ option in the ¼Find½ dialog box. See Appendix D of the $i$User's Guide$i$ for information on how to use GREP. READING LABELS: Normally your labels do not need to be enclosed in double quotation marks ("), but if you want to read labels that contain spaces, tabs or commas, you must enclose them in quotation marks. Use two double quotation marks in a row ("") to denote a quotation marks within a label. $$Startup script Using Asymptote The startup script is a special script Asymptote executes every time it starts up. You can use the startup script to change the default variables of the $i$graphics environment$i$. Make changes to the startup script when you want to reconfigure Asymptote to suit your needs. The startup script is just like any other script except that Asymptote runs it automatically when it starts up (unless you have turned this preference off). After the startup script runs, Asymptote records the state of the $i$graphics environment$i$. Later, when you select $i$Run˚Recorder$i$, Asymptote resets the variables of the $i$graphics environment$i$ to the values it had when the startup script finished running. In this way you can use the startup script to change the default values of various variables such as the font, graph frame, or pen size. In order for Asymptote to find the startup script, it must be named ¾Asymptote Startupà and it must be in the same folder with Asymptote. If you donàt have a startup script, you can create a new one by selecting File New to open a Text Editor Window. If you create a new startup script, be sure to name it ¾Asymptote Startupà and save it in the same folder as Asymptote. You can modify the startup script and make changes to it in a Text Editor Window. SEE ALSO: $i$graphics environment$i$ $$Graphics Environment Using Asymptote Asymptote uses the current values of various parameters when it draws text, lines or points. These parameters are called the $i$graphics environment$i$. They are: scale ± sizes of points, labels and tick marks see: $b$scale$b$ default: 1.0 rotation ± rotation of points and labels (CCW in ¡) see: $b$rotation$b$ default: 0.0 fillpattern ± pattern for filling points and polygons see: $b$fillpattern$b$ default: 1 (black) penpattern ± pattern for drawing lines see: $b$penpattern$b$ default: 1 (black) pensize ± thickness of the pen when drawing lines see: $b$pensize$b$ default: 1.0 pencolor ± color of all graphics and text see: $b$pencolor$b$ default: black pendash ± dash pattern to use when drawing lines see: $b$pendash$b$ default: solid penmode ± transfer mode for graphics see: $b$penmode$b$ default: 1 (opaque) textmode ± transfer mode for text see: $b$textmode$b$ default: 1 (opaque) fontname ± font for labels see: $b$fontname$b$ default: Times pointsymbol ± symbol to plot at each point see: $b$pointsymbol$b$ default: 4 cross Before you issue a command that draws any graphics (i.e. lines, points or polygons) or labels make sure that the parameters of the graphics environment are set the way you want them to be set. Use the $i$Status Window$i$ to see what the current values are. You can change the default values of the $i$graphics environment$i$ using the $i$Startup Script$i$. SEE ALSO: $i$Startup Script$i$ $$Variables & Constants Using Asymptote Variables and constants make it easier to enter commands and write scripts. There are two types of variables in Asymptote, user variables, which you define and control, and Asymptote variables, which Asymptote defines and controls. You can view the current values of all variables in the $i$Variables Window$i$. Constants are values set by Asymptote that never change. You use constants most often as the arguments to commands to make commands easier to read. Letàs take a look at how you can use variables and constants in your Asymptote scripts. $b$USER VARIABLES: ________________________________________$b$ If you want to define your own variables, use the $b$set$b$ command. See the $b$set$b$ help page for more information. $b$ASYMPTOTE VARIABLES:____________________________________$b$ When Asymptote starts up it creates a number of variables which you can use to make your commands and scripts more flexible. Many of these variables are variables of the $i$graphics environment$i$, such as the current size of the pen or the current position of the pen in graph coordinates. Other variables are the current number of points or the x and y limits of your graph. Asymptote automatically updates the values of these variables to reflect current conditions. For example, to move the pen to the lower left corner of the graph frame you could type the command moveto xleft ybottom which uses the variables xleft and ybottom, the x and y coordinates of the bottom left corner of the graph frame. The advantage or writing the moveto command this way is that it moves the pen to the lower left corner of the graph frame regardless of the limits of the graph. In another example, you could use the variable scale, to change the scale factor to twice its current value with the scale command as follows: scale scale 2 * Issuing the scale command this way has an advantage because no matter what the current scale factor is, the new scale factor will be twice as big. For example, you can use this command to draw a title on the graph twice the size of the tick mark labels. You can restore scale to its original value with the scale command as shown below: scale scale 2 / The following is a list of all Asymptote variables and the commands you can use to change their values. $b$Command$b$ $b$Value$b$ x ± x position of the pen in graph coordinates y ± y position of the pen in graph coordinates gx ± x position of the pen in page coordinates gx ± y position of the pen in page coordinates xleft ± left side of graph (in graph coordinates) see: $b$graphlimits$b$ xright ± right side of graph (in graph coordinates) see: $b$graphlimits$b$ ybottom ± top of graph (in graph coordinates) see: $b$graphlimits$b$ ytop ± bottom of graph (in graph coordinates) see: $b$graphlimits$b$ gleft ± left side of graph (in page coordinates) see: $b$graphframe$b$ gright ± right side of graph (in page coordinates) see: $b$graphframe$b$ gbottom ± top of graph (in page coordinates) see: $b$graphframe$b$ gtop ± bottom of graph (in page coordinates) see: $b$graphframe$b$ pleft ± left edge of the page (in page coordinates) see: $b$graphframe$b$ pright ± right edge of the page (in page coordinates) see: $b$graphframe$b$ pbottom ± bottom of the page (in page coordinates) see: $b$graphframe$b$ ptop ± top of the page (in page coordinates) see: $b$graphframe$b$ npts ± current number of points see: $b$npts$b$ scale ± maximum number of points see: $i$Memory Use$i$ scale ± current scale factor see: $b$scale$b$ rotation ± current rotation (in degrees) see: $b$rotation$b$ pensize ± current pen size see: $b$pensize$b$ penmode ± current pen transfer mode see: $b$penmode$b$ penpattern ± current pen pattern number see: $b$penpattern$b$ fillpattern ± current fill pattern number see: $b$fillpattern$b$ startline ± current start line to read see: $b$datalines$b$ endline ± current end line to read see: $b$datalines$b$ startcolumn ± current starting column to read see: $b$datacolumns$b$ endcolumn ± current end column to read see: $b$datacolumns$b$ notation ± current notation format see: $b$notation$b$ digits ± current number if significant digits see: $b$digits$b$ $b$CONSTANTS:____________________________________________$b$ When Asymptote starts up, it defines a number of constants for you. As mentioned above, you can't change a constant because they have special values that make typing script commands easier. For example, the single argument to fillpattern is a pattern number 0 through 38. To set the fill pattern to a light gray pattern, you could type the command like this: fillpattern 23 Or, you could type the command using the constant lightgray, which Asymptote has set equal to 23. Using the constant, the command becomes fillpattern lightgray which is much easier to read and to remember. The following table lists all Asymptote constants and some examples of how you can use them in commands. $b$Name$b$ $b$Value$b$ $b$Example of Use$b$ open 0 pointsymbol 4 open cross 1 star 2 filled 3 belowleft 1 drawlabel belowleft This is a label below 2 belowright 3 centerleft 4 center 5 centerright 6 aboveleft 7 above 8 aboveright 9 bottom 1 drawaxis top line inside parallel nolabels left 2 drawframe parallel perpendicular nolabels top 3 right 4 ticks 1 noticks 0 inside 1 outside 2 line 1 noline 0 parallel 1 perpendicular 2 nolabels 0 none 0 fillpattern none black 1 penpattern black darkgray 3 gray 4 lightgray 23 white 20 vertical 8 horizontal 27 diagonal 28 squares 11 bricks 12 opaque 1 textmode opaque transparent 2 penmode transparent reversed 3 erase 4 inverted 5 clear 6 overlay 7 whiteout 8 solid 0 pendash solid dot 1 pendash dot long dot short short 4 long 8 decimal -2 notation decimal float -1 general 0 default 1 scientific 2 ddmmss 3 hhmmss 4 true, yes, on 1 fullscreen true false, no, off 0 closed 1 plotpolygon closed