That’s the reason for the vast versions of SPICE available now decades after the original was released, not all of which are as open or free as we might like. Qucs is a GPL circuit simulator.

However, there is a new free option after ... you can set ranges for various circuit components, tell the program what you want to optimize, and it will compute the best values for you.

JSpice is a simple electrical circuit simulator written in Java with simple GUI and extended graphing capabilities ... The snippet for drawing the circuit layout uses complex conditioning which ...