.TRAN Simulation of Laplace Source "BesselLP" depends on simulation time

E1 LaplaceLP(6,1e5) with stimulus “pulse 0 1 10µ 1n 1n 50µ 100µ” generates erratic over/undershoots with results depending on simulation time:

Yep. A 6th order is a difficult filter in the time domain. You’ll probably want to go to Edit=>Preferences=> and uncheck “Fast(less accurate) Math”


“Unchecking Fast Math” works perfectly. Thanks Mike.

Is it a good idea to run first simulations with and w/o “fast math” and compare results to decide later - for long running simulations - whether the fast way will do the job?
Can you give caveats for nasty types of circuits?

If answering my questions detract you from improving QSPICE, please ignore them.
I like very much, what I see up to now.

One comment about your fabulous response time - over the week end: Top
and thank you again for creating a better “Spice”.

I use “fast math” all the time. Well, unless it doesn’t work, then I uncheck it.