Andrew Beckett
Senior Fellow
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Life, don't talk to me about Life...
Posts: 1742
Bracknell, UK
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All three errpresets have been revamped in IC50, to optimise them using tests on lots of circuits, and also to take into account the new Multi-Interval Chebychev option (the "highorder" option) for improving the numerical noise floor that came in for PSS in IC50.
Prior to IC50, the errpreset settings were not particularly good and so it was usually best to set some of the individual settings:
reltol: 1e-4 or 1e-5 relref: alllocal method: gear2only steadyratio: 0.001 (I think that's the default). you might also want to tighten vabstol/iabstol a little.
However, your mileage may vary, and so you should _think_ about the settings rather than just wildly guessing! See Ken's book for more advice on the effect of the transient/DC tolerance options.
In IC50 we'd generally recommend you set the errpresets, and only override them if you need to (and know what you're doing).
Regards,
Andrew.
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