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Is there anyone here tried to make corners simulation using the command 'altermod' in ngspice?

That would be a really roundabout way of doing a corner simulation.  Why do that instead of using the corner simulation models directly?

I want to run more than one corner in the same run, I found in the manual that altermod command do that but I didn't figure out how to do that.

My advice is not to do multiple corners in one run.

<@U016EM8L91B> I wanted to ask you about this why not? Using such technique usually speeds up the simulation. Because it doesn't have to rebuild the circuit in memory only loading models.

<@U0252QQUBUJ> I think let's follow <@U016EM8L91B> advise for now.

<@U01EK2VDMDG>: Ideally, yes, but in practice it's just a pain to work with ngspice's built-in command language, and it makes everything unportable (e.g., to xyce).

Once upon a time, the tclspice version of ngspice worked really well for those kind of things, but it has been broken for years.

<@U016EM8L91B> I used to do that with most of commercial tools: ELDO, Spectre, HSPICE, etc...

<@U016EM8L91B> I understand that whatever <@U0252QQUBUJ> doing is not going to be portable to other tool like Xyce. But is there any limitations in the model cards files that I should look out for?

<@U01EK2VDMDG>:  As far as I'm aware, there are no particular issues currently for running with ngspice other than the fact that a lot of the models are binned over narrow L and W ranges and are not at all well characterized outside of those ranges.