skrf.network
skrf.frequency
skrf.networkSet
skrf.plotting
skrf.taper
skrf.calibration.calibration
skrf.calibration.deembedding
skrf.vi
skrf.vi.vna
skrf.vectorFitting
skrf.qfactor
skrf.time
skrf.circuit
skrf.media.device
skrf.mathFunctions
skrf.tlineFunctions
skrf.instances
skrf.constants
skrf.data
skrf.util
Covariance matrix.
shape of output will be (nfreq, 2*nports**2, 2*nports**2)
ndarray