guen_gn:

Here the keyword is output: does it mean this parameter is equivalent to out_features in pytorch nn?


Yes, that’s correct.



 guen_gn:

Then what should be “in_features*”?


It depends on your use case and the number of features of your input.
E.g. if the input to your model has a shape of [batch_size, 10], then the first nn.Linear layer would use in_features=10. If you stack linear layers, then the out_features of the previous layer are the in_features of the next one.