From: Mike Kost <mike@ta...>  20060801 12:49:37

Stephan, > If not, any suggestions for better accuracy with fewer points? > > I've already manipulated the integration method and gotten large > > improvements over the 2nd order trapezoidal (I'm on a 4th order Gear at > > the > > moment). > > In your case you would like to limit the "maxstep" to a smaller value to > get better accuracy, but few points only. Did I understand you correctly? Yes. That was the immediate solution that sprang to mind. I do not know enough about the simultaor internals to do more than speculate, but I suspect my problem originates from the fact that I'm using ideal relays. I am guessing that large maxstep values result in the simulator missing the actual close/open time and instead uses the nearest maxstep that is near the close/open event, but that the discrepency does not cause convergence problems so the simulator does not drop to a smaller step value. If this theory is correct, a better solution to the problem would be for the simulator to attempt to locate the actual relay / switch open/close time. This would be done as follows 1. Note current time 2. Calculate next timestep 3. If a relay / switch changes state during the timestep, use a binary search to get more accuracy on the switching point It's possible that the simulator is doing some form of this, but if it is, I do not understand why I seem to need a smaller "maxstep" value. Thanks for your time Stefan, Mike 