GraphyCalc is a 3d graphing calculator, allowing you to interactively explore 3d functions.

Nerdy Details: The formula you supply calculates the height *z* from the variables *x* and *y* between *-1* and *1*. Formulas are composed of arithmetic operators (*+ - * / ^*), built-in functions (*abs acos asin atan ceil cos exp floor log round sin sinc sqrt tan*), and constants (*E PI*).