So, how is everyone doing regression sims (a.k.a. corner sims) in ngspice, anyway? With

alterparam

statements inside

.control

blocks? Or is everyone just running their netlists through Python filters? It looks like

alterparam

can handle parameters, but what about models? Can you define a parameter for the

cnr

portion in

.lib <file> <cnr>

and use that? Ngspice's

alter

system looks pretty confusing. If everyone is just using scripts in their language of choice, I could understand.