ParaGraph: a parametric graphing calculator. ParaGraph can graph multiple functions at once, perform numerical calculus, find extrema, do log plots, plot polar graphs, fit curves to data, do basic vector operations, and much more.
While most people are accustomed to using dependant/independent variable equations (y = f(x)), parametric equations are more versatile sets of parameters - one parameter describing x, and one describing y. In ParaGraph, all parameters are functions of z, so the two parameters are x = f(z) and y = f(z).
So, if you want a tool to help you create your graphs in just a few steps, give this program a try and check out if it can offer you what you need.

The license of this software is Free, you can free download and free use this calculator software.