This is an automatic grapher. Put an equation in the f(x)= box and hit enter. The graph will appear in the window. Clicking on the Postfix button will make the postfix form of the expression appear below the dialog box.

Examples of equations:

Here are the functions:
sin = s()
cos = c()
abs val. = a()
log = l()
sqr. root = r()

Note that the whole program is not entirely mine. The parts of the program that I did not write include the parts that get the individual answers for each "x" value and display them to the screen, as well as anything else that gets displayed to the screen.