Gnucap is a general purpose circuit simulator. It performs nonlinear dc and
transient analyses, fourier analysis, and ac analysis. Gnucap is not based on
Spice, but some of the models have been derived from the Berkeley models.
Unlike Spice, the engine is designed to do true mixed-mode simulation. Most
of the code is in place for future support of event driven analog simulation,
and true multi-rate simulation.