MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming
KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
GNU Octave - GNU Octave is a programming language for scientific computing.
Proteus PCB design - Proteus PCB design combines the schematic capture and ARES PCB layout programs to provide a...
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.
EasyEDA - EasyEDA - Web-based EDA suite; runs in browser.