control.phase_crossover_frequencies

control.phase_crossover_frequencies(sys)

Compute frequencies and gains at intersections with real axis in Nyquist plot.

Call as:

omega, gain = phase_crossover_frequencies()

Returns:

omega: 1d array of (non-negative) frequencies where Nyquist plot

intersects the real axis

gain: 1d array of corresponding gains

Examples

>>> tf = TransferFunction([1], [1, 2, 3, 4])
>>> PhaseCrossoverFrequenies(tf)
(array([ 1.73205081,  0.        ]), array([-0.5 ,  0.25]))