What are some alternatives?
When comparing wxMaxima and GnuPlot, you can also consider the following products
GNU Octave - GNU Octave is a programming language for scientific computing.
Matplotlib - matplotlib is a python 2D plotting library which produces publication quality figures in a variety...
Wolfram Mathematica - Mathematica has characterized the cutting edge in specialized processing—and gave the chief calculation environment to a large number of pioneers, instructors, understudies, and others around the globe.
GeoGebra - GeoGebra is free and multi-platform dynamic mathematics software for learning and teaching.
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming
SciDaVis - SciDAVis is a free application for Scientific Data Analysis and Visualization.