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You may write a script using the ngspice .control language. For a tutorial please see https://ngspice.sourceforge.io/ngspice-control-language-tutorial.html

I use a system called CACE (which unfortunately I have not finished porting to work outside of the Efabless platform) which runs many small simulations, collects the data, and then runs them through Octave (the open-source Matlab-compatible app) to do the calculations of DNL, INL, SNR, etc. I'm not sure how easily you can make use of the scripts themselves, but here they are if you want to look at them.

@Tim Edwards Thank you, let me have a try at it