Z-Plot

Z-Plot is a free plotting software that allows you to visualize a multitude of mathematical functions and curves.

The software has a powerful mathematical formula interpreter, that also allows the user to handle complex numbers, easily. The display can be switched from 2D to 3D mode. Additionally, diagrams can be made from a data table.
Selected program features:
-3D/2D display that be rotated and scaled freely
-The common mathematical functions are supported
-Calculating with complex numbers is supported by any mathematical operation. Additionally, it is possible to determine the real part, imaginary part, argument and absolute value of complex expressions.
-Choose between linear and logarithmic axes scaling.
-Integrated calculator including numerical integral and differential calculus
-Make diagrams from a data table
-With detailed online help.