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GRAPHICS Graph menu The REGULAR selection will graph the data with the labels you have entered in the data entry area along the "X" axis. The type of graph will depend on the selections you have made in the "styles" area. Up to 6 variables may be chosen. You may plot some against the left axis and some against the right axis. The HORIZONTAL graph option puts the labels on the "Y" axis and the values along the "X". You can not have a right side axis for this type of graph. "XY" graphs allow up to 6 pairs of variables to be used. You must select your data a pair at a time. The first one chosen of each pair will be the "X" value of the point and the second will be the "Y". You may repeat the same selection between pairs so that you can have several variables graphed against the same "X". There are no XY bar graphs. You can not have a right side axis. HI LO graphs are stock market graphs. The first 3 variables chosen will be displayed as a high low close type of graph. The remainder of the 6 possible graphs will be shown as selected on the styles section. You can use right side axis which allows you to graph volume on the same graph as stock prices. You can have a hi low graph with only 2 variables. In this case the data represents simply a high and low but no close. PIE CHARTS. You may have up to 4 pies on the screen. Simply specify the correct number of variables. A special case exists for 2 pie charts if you have selected "component pies" from the features menu. In this case the second variable will be assumed to be an explosion of the first pie segment. BUBBLE GRAPHS require 3 variables to be chosen. The first specifies the "X" value of the point. The second specifies the "Y" value of the point and the third specifies the relative area of the bubble. OPPOSED BARS require 2 variables which must be positive. If logs are on they are ignored. Opposed bars are good for comparing similar data against one another. an example might be the population of the U.S.A. by age group where one variable represents males and another females. The key feature of opposed bars is that there is no offset between the variables. One peculiarity of the implementation comes up in rescaling. The second variable is treated as being negative by the program. Thus the minimum value is shown as a negative. This is a requirement so ensure that you enter a negative for the minimum, even though it will be printed as a positive. FLOATING BARS require 2 variables for each bar plotted. The first represents the minimum of the floating bar and the second the top. Like XY graphs you will continue to be prompted for input until you fail to enter 2 variables. This is not an XY graph however. The X-axis is scaled by the labels just as for a regular graph. HORIZONTAL FLOATING BARS are the same as regular floating bars except that the graph is done horizontally. POLAR PLOTS are a variation on XY graphs. Selection procedures are the same. The difference is that the variables chosen give the angle in radians and distance of the point rather than "X" and "Y" respectively. 3D BARS allow for up to 18 points in each factor. The data is displayed with a three dimensional aspect. The variables are displayed behind one another with the first variable chosen being the front variable. In some cases data points will not be seen since the column will be entirely hidden. No right side scaling may be used. STAT GRAF These procedures are particular graph types used for analysis. A STAR GRAPH produces a chart describing the physical values of several variables at each of several points. There should be no negative values. For each point a series of lines are drawn starting at 3 O'clock and then working counterclock wise around the point. The length of the lines represents how high the value of the variable is for that point. The minimum value of the line is set to 20 percent of the maximum. A SUN RAY GRAPH is similar in concept. In this case each line is the same length but the line is cut at a value indicating relative length.If the line is cut exactly in the middle then the point has a value for that variable which is at the mean for all points. A BOX WHISKER GRAPH requires the selection of a variable and a category variable. The box and whisker are then drawn for values from the first variable where the categorical variable is at a certain level. The box and whisker is a regular style graph. The box has it's top valu at the 3rd quartile point and its bottom at the first quartile. The box is bisected by a line at the median. Extending out from the box at top and bottom are the whiskers. These reach out to the highest and lowest point in the data variable for a given level of the categorical variable. The NOTCHED BOX WHISKER is the same except that there is an additional piece of information given. There is a notch in the box which covers a 95 percent confidence limit on the median. The depth of the notch is proportional to the number of elements in the variable with that value of the categorical variable. XYZ graphs are similar to XY graphs. The main difference is that there are three coordinate axes, and you must pick the variables in threes. Another change is the lack of a legend. No legend is put on the right of the graph to allow for the extra width taken by the three dimensional graph. For labelling you will need to use the custom labelling feature. For XYZ graphs you may select point, line and bar options. The bar option does not actually produce bars in this situation. Instead, a perpendicular is dropped to the XY plain. This gives a better indicator of the height of the point. Z function plots are three dimensional graphs of a function of the form Z=f(X,Y). You will be asked to specify the graphing limits for X,Y and Z. You will then be asked to specify the equation and then the number of steps to make in each of the X and Y directions. The greater the number of steps, the finer the graph but also the slower the graph. With 50 steps in each direction there are 5000 calls to the parser and this can be a slow process. After setting the parameters you will be asked whether you want hidden lines or not. The default is for no hidden lines (ie a wire frame). The next option is a combination of the previous 2. The main use for this option is to examine actual points from a regression against the 3D regression surface provided by the computer. The Z Data plot assumes that all of the data in the editor represents Z values for particular combinations of X and Y which are uniformally spaced. It does not know what the minimum and maximum X and Y values are. You will be asked to specify the maximum and minimum for X,Y, and Z just as for a function plot. You will not need to specify the number of steps since that is determined by the amount of data available. As an example consider a select mortality table as used by an insurance company. There would be rates of mortality for each issue age and for each of the first 15 durations since the policy was issued. If we were to examine mortality rates for ages 15 to 75 and for durations 1 to 15 the data would be set up as follows. There would be 15 columns in use. Each row in the column would represent the mortality level at a given age for that duration. There would be 61 rows to handle the various ages. The number of steps would internally be set to 60 and 14 with this data. For all of the XYZ graph types the "right side" title is used to label the "Y" axis. SETTINGS The settings menu allows you to define how the graph will look. The palette setting allows you to set the palette for the graph User Fill allows you to define up to 6 fill patterns for use by the program. These may be saved and reloaded for the next use of B/STAT. They are not compatable with fill files from DEGAS. Styles allows setting the line style fill pattern and point style. It also allows you to turn on lines bars or points. All 3 can be on for any given variable. Pie Style allows you to set colors and fill styles for pies as well as whether a slice is exploded. Background allows for setting a background fill pattern over which the graph is drawn. There are two types of fill, Full and Partial. For Full the entire graph area is filled in. For Partial only the part of the graph between the axis lines is filled in. The selection of fill style is the same as for pie or bar styles. Axes allows turning scaling or axes on and off as well as selecting the color to be used. Tic marks may be turned on or set to go in or out. Titles allows you to enter the titles to be used on the graph. Title Fonts allows you to select the color and style of the titles and scales used in the graph. Tic size allows the setting of major and minor tic lengths. Features Boxed means that for regular and horizontal graphs a line will be drawn to close in the graph. Rt side axis will allow a right side axis on regular graphs. Stacked will give stacked bar graphs and area graphs for line graphs. Filled will cause the area between lines to be filled in. It can not be combined with stacked. Vals above will cause the value of the point to be displayed above it for regular and horizontal graphs. For Pie charts the values will be printed below the pie label. Legend will cause the legend for each variable to be displayed. If turned off then the graph will be larger but you will have to use custom labelling to define what the variables are. Log X causes the X axis to be on a LOG basis. Log Y does the same for the Y axis. Proportional Pie means that if more than 1 pie is shown on the screen at once there relative sizes will be determined by the total of the values in each pie. This is quite usefull when comparing 4 years of sales data. Component Pie. When 2 variables are selected for a pie graph this option causes the second variable to be taken as a subset of the first pie sector. The values in the second variable are displayed as a stacked bar set to the right of the pie. Pie Percent will cause the percentage each pie slice represents to be printed in the pie slice. The percent is rounded to the nearest whole percentage. Redraw will redraw the graph if the reset graph option is off. Grids These two options turn on horizontal and vertical grids and the Z grids. There is also a "zero line" option to ensure that a line is drawn at the zero point even if no grids are displayed. While a graph is on screen labels may be added by double clicking where you want them to appear. You will be required to select the font and size for the label just as for titles. You have the option of adding an arrow. Simply click where you want it to point. These labels may be dragged on the screen. To remove a floating label, double click on the label. You are now asked "What to Change?". This can be either font, text, or arrow. You can remove the label by selecting text and erasing the existing text. A label with no text is simply removed from the list of labels. If you choose arrow you can either add an arrow if one does not exist or move the anchor point for an existing arrow, or remove the arrow. You may also resize the graph. This is done by placing the mouse in the lower right corner of the graph and then draging the mouse. The graph can be reduced to 1/4 its original size. You may also reposition the smaller graph by holding down the mouse button while the mouse is inside the axes. The menu bar displayed while a graph is on screen allows you to save or print the graph. The "Save" menu items allow three forms of saving the screen image. The first is as a DEGAS compatable uncompressed image. The second is as a ".IMG" file which can be used by desktop publishing programs. With a color system you will be asked if you want a color IMG file. Many desk top publishing programs can not handle a color file so you can put out a monochrome version of the screen. The IMG files produced by BSTAT are compatable with IMG files on MSDOS machines. They can therefore be used with Wordperfect version 5.0 on these machines. Note that IMG files are bit image files. The quality of reproduction is not as good as using a GDOS print to the same physical size area. The third choice is as a metafile. Metafiles can be read by programs such as Easy Draw and many desktop publishing programs such as Pagestream, Calamus and the Timeworks Desktop Publisher (TWDTP). To read the files into TWDTP you will need to select the "GEM DRAW" option in TWDTP. When printing you have three options. First you can print the screen using the built in Atari screen dump utility or one which you have loaded yourself. The second option is usefull only for 9 pin Epson printers. This option uses the Epson plotter mode to ensure properly scaled pictures. It also only works with the monochrome monitor. The third choice uses GDOS if you have it to plot to the printer. The text on the graph will not usually look quite the same as on the screen since many GDOS fonts are proportional and the default screen fonts are not. Also some of the printer fonts are not quite the same size as the screen fonts. The remaining choices are to adjust GDOS printing. The GDOS settings item allows you to decide on the width and height of the graph on the paper. Various GDOS drivers as well as printers will start graphs in different places. Thus setting the starting position offset to be zero may not put the graph at exactly the edge of the paper. Many Epson clones start graphics 1/4 of an inch from the edge. You should therefore do a GDOS print of a graph with the standard settings. Before doing the print turn on "GDOS box". This will result in a box being drawn around the edges of the graphing area. You can then use the resulting positions to establish a vertical and horizontal offset for your particular printer. The "GDOS Device" Selection allows you to set the device ID that the program uses to that which you have set in your ASSIGN.SYS file. Most users will never have to use this setting. The default in B/STAT is device 21 which is the usual standard. This choice is for those lucky individuals who have more than one printer in use or who have a plotter which is supported by GDOS. "GDOS Rotate" allows you to print the graph in landscape mode as opposed to the normal portrait orientation. The miscellaneous menu contains only one unusual feature. The "Keep Labels" option when chosen (the default) ensures that the custom labels will be kept when you return to the graph selection screen. To get rid of them all, simply deselect the option. Also on the miscellaneous menu is the selection for "Legend Box". When this is selected the legend may be dragged around on the graph until you release the button. If the option has already been selected then reselecting it will result in returning to the default setting. When selected you may further move the legend by selecting "Move Legend". Reset Graph is normally set. If off then you can redisplay the graph from the previous menu simply by doing a redraw.