Blender - Blender is the open source, cross platform suite of tools for 3D creation.
SciDaVis - SciDAVis is a free application for Scientific Data Analysis and Visualization.
FreeCAD - An open-source parametric 3D modeler
GnuPlot - Gnuplot is a portable command-line driven interactive data and function plotting utility.
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming
Matplotlib - matplotlib is a python 2D plotting library which produces publication quality figures in a variety...