Don't forget to press ESCAPE to remove a help screen.
This allows you to plot previously created functions.
You can select up to 10 functions and one data set, see the ones you've selected, deselect some or all of those selected, set the x and y bounds, and graph the selected functions.
This allows you to select up to 10 functions and one data set to be graphed. You can tell whether functions have been selected by looking at the second line on the screen. If there is an asterisk ("*") showing near the end, a function has been selected.
If you only want to select one function, place the high lighted bar over it, and press RETURN or ENTER.
If you want to select more than one function, press the F5 key after placing the highlighted bar over the function.
If you press ESCAPE, no functions will be selected.
This displays the functions which have been selected for plotting.
You can tell whether functions have been selected by looking at the second line on the screen. If there is an asterisk ("*") showing near the end, a function has been selected.
This allows you to deselect functions already selected.
You can tell whether functions have been selected by looking at the second line on the screen. If there is an asterisk ("*") showing near the end, a function has been selected.
If you only want to deselect one function, place the high lighted bar over it, and press RETURN or ENTER.
If you want to deselect more than one function, press the F5 key after placing the highlighted bar over the function.
If you press ESCAPE, no functions will be deselected.
This allows you to deselect all the functions previously selected. You can tell whether functions have been selected by looking at the second line on the screen. If there is an asterisk ("*") showing near the end, a function has been selected.
This allows you to select the minimum and maximum values for x. The graph will then be restricted to this domain.
The current minimum and maximum values are displayed on the second line on the screen.
Either you can have the computer select the minimum and maximum values for y automatically, or you can override this with your own choices. The graph will then be restricted to this range.
You can tell whether the automatic feature is on or off, by looking at the middle of the second line on the screen next to "Auto y:". YES means the domain will be selected by the computer, and NO means you have selected it.
This will plot all the selected functions using the domain and range on the second line of the screen.
You will see a "Please Wait" message, which may be there for some time, depending on your machine and whether there is a numeric coprocessor present.
When the graph appears, a flashing cursor is placed in the middle of the screen and its x,y coordinates are printed at the top left hand side. You can move the cursor around the screen using the arrow keys. Initially the step size is large. Pressing the "-" key reduces the step size to 1, while the "+" key restores the larger step size.
Pressing the "F" key will fill (or flood) the screen from the cursor out to the first solid boundary. This is not reversible. Pressing the "x" key places a cross at the cursor position, while "X" removes a cross.
To get a printout of the screen press the "P" key.
When you have finished looking at the graph you can return to the main menu by pressing the ESCAPE or RETURN key.
When the graph appears, a flashing cursor is placed in the middle of the screen and its x,y coordinates are printed at the top left hand side. You can move the cursor around the screen using the arrow keys. Initially the step sizes are large. Pressing the "-" key reduces the step size to 1, while the "+" key restores the larger step size.
Press PgDn for more help on graphing.
If you want a printout of the screen (and you have an appropriate printer online) press the "P" key.
Press ESCAPE when finished reading this help.
Use this to create functions of the type y=f(x).
If you press the INSERT key, a list of functions is displayed. You can use and edit these, or create your own function from scratch. You will be expected to supply a unique function name.
There are two points to remember. Exponentiation is represented by the "^" key, so that 10^2 = 100. Also x^3/2 = (x^3)/2 NOT x^(3/2).
If you want to create a function like
sin(x)/x if x
f(x) =
1 if x = 0
then use the following construction
ifne(x,0,1){sin(x)/x}
which can be read "if x is not equal to 0, use sin(x)/x else use 1".
Use this to create polynomials of the type
n=N n
f(x) =
a(n)x
n=0
where the a(n) satisfy a two term recurrence relation of the form
a(n+2) =
(n)a(n+1) +
(n)a(n), for n = 0, ... , N-2,
with given a(0) and a(1).
These are the types of partial sums that occur when solving second order ODEs using a power series method.
You will be asked for
(n),
(n), a(0), a(1), and N. You will be expected to supply a unique function name.
If you happen to have a one term recurrence relation, say
a(n+1) =
(n)a(n), for given a(0) =
it can be converted into the following two term recurrence relation:
a(n+2) =
(n+1)
(n)a(n), subject to a(0) =
and a(1) =
Use this to create parametric curves of the type
x=x(t), y=y(t).
If you press the INSERT key, a list of functions is displayed. You can use and edit these, or create your own function from scratch.
You will be asked for x(t), y(t), and the starting and ending values of t. You will be expected to supply a unique function name.
After this, the program will compute the "extent" of the parametric curve, i.e. the minimum and maximum x values, and you can use these to change the existing x bounds.
Use this to create polar curves of the type
r=r(t),
where t is the angle
. In fact, these are special cases of parametric equations where
x(t) = r(t)cos(t), and y(t) = r(t)sin(t).
If you press the INSERT key, a list of functions is displayed. You can use and edit these, or create your own function from scratch.
You will be asked for r(t) and the starting and ending values of t. You will be expected to supply a unique function name.
After this, the program will compute the "extent" of the parametric curve, i.e. the minimum and maximum x values, and you can use these to change the existing x bounds.
This allows you to delete functions already created.
If you only want to delete one function, place the high lighted bar over it, and press RETURN or ENTER.
If you want to delete more than one function, press the F5 key after placing the highlighted bar over the function.
If you press ESCAPE, no functions will be deleted.
Use this to edit an existing function.
Select the function to be edited by moving the high lighted bar over the function and pressing RETURN.
This allows you to look at all the existing functions. You can also use this to select functions.
You can use this to create a text file to control the graphics output, in place of using the commands under the PLOT FUNCTIONS menu.
If you press the INSERT key, the existing commands are displayed.
Allows you to edit a text file.
There should be only one command per line.
To duplicate a portion of text :
1. Place cursor at start of text to be copied.
2. Press F5.
3. Move cursor to end of text to be copied (text should be highlighted).
4. Press DELETE.
5. Press INSERT.
6. Move cursor to place were text is to be copied.
7. Press INSERT.
Deletes an entire text.
This plays (executes) a previously created text file.
Allows you to load previously saved functions and text from disk.
Allows you to save created functions and text to disk.
Allows you to change disk drives.
Allows you to change directories on the current drive.
Gives various disk information, viz. the current drive, the current directory, and the total and remaining free space on the current drive.
Lists all the files in the current directory.
This allows you to identify the graphics printer hooked up to your system. The choice is simple - either EPSON compatible or LASERJET.
These are the instructions you should have read when you first ran the program.
The wonderful band of people who don't get enough recognition.
Kwa Heri.
(Swahili for "Good Bye"!)
Use this to create, delete, and edit, functions of the type
y = f(x), (function)
n=N n
y =
a(n)x , (polynomial, partial sum)
n=0
x = x(t),
y = y(t), (parametric function)
r = r(t), (polar function).
This allows you to create, edit, delete, and execute a "text" file. This is a command file that executes a limited set of commands.
This is where functions and text are saved and loaded, and other disk oriented chores are performed.
Miscellaneous operations which don't belong anywhere else.j*
MATHEMATICAL FORMULA EXPRESSION TO USE
e
exp(n)
x
sqr(x) or x^2 or x*x
x sqrt(x)
abs(x)
arc cos(x) acos(x)
arc sin(x) asin(x)
arc tan(x) atan(x)
log(x) = ln(x) log(x)
sgn(x) signum(x)
PRESS PgDn (Page Down) to see more.
MATHEMATICAL FORMULA EXPRESSION TO USE
f(x) if x
g(x) = ifne(x,a,c){f(x)}
c if x = a
f(x) if x < a
g(x) = ifl(x,a){f(x)}
0 otherwise
f(x) if x > a
g(x) = ifg(x,a){f(x)}
0 otherwise
f(x) if a < x < b
g(x) = ifb(x,a,b){f(x)}
0 otherwise
These are the commands that are recognized when you "Play Text".
graph f(x) : Plots the graph of the function f(x).
erase f(x) : Erase the graph of the function f(x).
wait : Wait for a key stroke.
print : Send the graph to a printer.
vertical a : Draws a vertical solid line at x = a.
asymptote a : Draws a vertical dotted line at x = a.
; : The start of a remark.
data dots : Plots the data with dots.
data lines : Plots the data with lines.
data to x : Plots the data with vertical lines.
domain a b : Sets domain to a < x < b.
range auto : Sets range to automatic.
range a b : Sets range to a < y < b.
There should be one command per line.
Only one domain and one range command per text file. If more than one exists, only the last one is recognized.
Allows you to load a previously saved data set from disk.40
Allows you to save a created data set to disk.
Save Data Help
This allows you to create a data set. Only one data set can be in the computer at one time. At present the maximum number of data points is 150.
The format of a data set is an x value and its corresponding y value.
Use this to edit the data.
This will delete the entire data set.
Allows you to reset the size of the data set. The initial value is 150. The largest data set you can enter will depend on the available memory in your machine, but cannot exceed 999. However, if you use a large amount of memory for your data set, there may be insufficient room remaining for other features of the program.
Use this to create polynomials of the type
n=N n
f(x) =
a(n)x
n=0
where the a(n) are given explicitly.
You will be asked for a(n) and N. You will be expected to supply a unique function name.
If you want to create a(n) which are zero if n is odd, don't forget functions like cos(n*
This allows you to have the data reformated if there is enough room.
This will print the data to the selected printer.
This allows you to view the data without editing it.
This allows you to select the maximum number of decimal places displayed on the graphics screen. It is purely cosmetic and has no bearing on the accuracy of the calculations. Initially it is set to 4.
If a function approaches infinity, its value is replaced by a specified numerical value. This option allows you to set this "infinity" to any value between 1 and 999,999,999,999,999. The default value is 1,000,000.
When the program plots a graph, it generally starts at the left hand side of the screen, plots a value, moves over an "increment" number of pixels, plots another value, and joins them with a straight line. The smaller the increment, the more accurate the graph, but the longer the time required to draw it. This option allows you to change the increment from the default value of 2 to a number between 1 and 10.
This allows you to evaluate an existing function for various values of x. The result is placed in data as a table. 100 function values (each up to 8 decimal places) are displayed.
This will allow you to find the first minimum in the data set.
This will allow you to find the first maximum in the data set.
This will allow you to find the first sign change, or zero, in the data set.
If you set the delay, then, when graphing, there will be a delay between each point plotted. Normally you will not want to set the delay.
This is where you can create, edit, and delete a data set.
This will allow previously created projects to be loaded in from disk. Project filenames have the extension PRO.
(.txt)