Siconos  SICONOS is an Open Source scientific software primarily targeted at modeling and simulating non-smooth dynamical systems (NSDS): Other applications are found in Systems and Control (hybrid systems, differential inclusions, optimal control with state constraints), Optimization (Complementarity problem and Variational inequality) Biology Gene regulatory network, Fluid Mechanics and Computer graphics, etc. The software is based on 3 main components  According to peer reviewed studies published by its developers, Siconos was approximately five times faster than Ngspice or ELDO (a commercial SPICE by Mentor Graphics) and 250 times faster than PLECS when solving a buck converter.