statetotransfer and transfertostate functions are missing output type choices

[Ilhan Polat]

In matlab for example, every now and then, we use

F = tf(G);
n,d = tfdata

Here, harold should have an option to select whether the individual system components or the system itself should be returned.

F   = statetotransfer(G)                # should give a genuine Transfer() object
n,d = statetotransfer(G,only_data=True) # should give the num and den entries instead

[Ilhan Polat]

This is implemented. The key name is output with choices system or matrices