Don't forget to press ESCAPE to remove a help screen.
This allows you to create, edit, delete, and plot functions.
This is where you can select new values for the parameters a, b, and c.
This will allow previously created projects to be loaded in from disk. Project filenames have the extension PRO.
The number (epsilon) you put in here is used by the integration technique (either Romberg Integration or Simpson's method), to determine when to stop subdividing the interval of integration. Epsilon represents the fractional accuracy, i.e. if the latest numerical approximation for the integral is within epsilon*old value of the old value, then the routine stops, and prints the latest numerical approximation. The minimum value for epsilon is .00001. The default value is .01. Thus, with the default value, if the actual integral was 100, the numerical routine would stop within .01*100 = 1 of 100. The smaller the value for epsilon, the slower the computation, but the greater the inaccuracy.
This is where you select the domain (x-values) and range (y-values) to be plotted.
Plots all the created functions (up to 2) using your domain and range. When the graph appears the following keys are active.
The "a"/"A" key decreases/increases the value of "a" by "ai".
The "b"/"B" key decreases/increases the value of "b" by "bi".
The "c"/"C" key decreases/increases the value of "c" by "ci".
The "END"/"HOME" key decreases/increases "ai" by a factor of 10.
The "DN ARROW"/"UP ARROW" key decreases/increases "bi" by a factor of 10.
The "PgDn"/"PgUp" key decreases/increases "ci" by a factor of 10.
The "i" key performs numerical Romberg Integration of the functions.
The "I" key performs numerical integration by Simpson's method.
The "r" key clears the screen and redraws the latest graph.
The "P" key prints the screen to the selected printer.
The RETURN key draws the function with the new values of "a", "b", "c".
The ESCAPE key returns you to the main menu.
Use this to create functions of the type y=f(x), which may also include parameters a, b, c. You can create up to two functions.
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 initial values for a, b, and c, as well as the range and domain.
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".
This allows you to delete functions already created.
To delete a function, place the high lighted bar over it, and press RETURN or ENTER.
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.
Allows you to load previously saved functions from disk.
Allows you to save created functions 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"!)
This is where functions are saved and loaded, and other disk oriented chores are performed.
Miscellaneous operations which don't belong anywhere else.
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 taken to draw it. This option allows you to change the increment from the default value of 5 to a number between 1 and 10.
(.txt)