To graph a function you have too use Reverse Polish notation.
example x,2,^ is the same as x^2
commas denote separate items 
ie. when the program comes across a comma it pushes all the proceding data onto the stack and sets the Holder varible to 0 if the preceding data is an operation it pops the two preceding values off the stack and does the operation to them; so if you have x,2,* the program pushes the x and 2 onto the stack and when it comes to the times symbol it pops the 2 and the x off of the stack and multiplies the x by the 2.

here are some more examples of equations.

x,2,* = x*2
x,2,^,2 * = x^2*2
x,3,^,x,2,^,- = x^3-x^2


When you click the value button the program will give you the Y value for the X value thats in the X Value Box.

This is my first Readme so if you can't get it to work email me at Bjwbell@netscape.net