@Holger Vogt does it make sense to perform

.disto

analysis using IHP Mosfet models or it is not supported ?

To be honest, I do not know. I have not heard about somebody using .disto for years now. It may be worth however to define some tests. There should be no basic show stopper.

@Holger Vogt thank you for answering the question. I have just tried it using a simple transmission gate circuit and the output vector contains only zeros. Whet I set the

f2overf1

optional parameter the analysis fails.

The manual (ngspice-43) says in chapter 11.3.3: Only a subset of the ngspice nonlinear device models supports distortion analysis. These are • Diodes (DIO), • BJT, • JFET (level 1), • MOSFETs (levels 1, 2, 3, 9, and BSIM1), • MESFET (level 1). So Verilog-A models like PSP are not supported.