SAPWIN (Symbolic Analysis Program for Windows) is a symbolic circuit simulator written in C++ for the Windows (95/98/ME/NT/2000) environment. Unlike more common numerical circuit simulators (such as SPICE), SAPWIN can generate analytical Laplace domain expressions for arbitrary network functions of linear analog circuits. The SAPWIN package also includes tools for schematic capture and graphic post-processing.
SAPWIN is available for free from its homepage at the University of Florence website.
SAPEC-NG (Symbolic Analysis Program for Electric Circuits - Next Generation) is the open-source successor to SAPWIN, written in C and designed for the Linux platform. It is currently in development and lacks schematic capture and a GUI front-end.