SapWin

Symbolic Analysis Program for Windows (SAPWIN) is a proprietary symbolic circuit simulator written in C++ for the Microsoft Windows operating systems Vista, 7.0 and 8.1. Unlike more common numerical circuit simulators (such as Simulation Program with Integrated Circuit Emphasis (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 free from its homepage at the University of Florence website.
SapecNG.
Symbolic Analysis Program for Electric Circuits - Next Generation (SapecNG) is the open-source software relative of SAPWIN, written in Boost C++ libraries and designed to be cross-platform. QSapecNG is a Qt-based graphical user interface (GUI) and schematic capture program for SAPEC-NG.