pyFDN.det_polynomial

pyFDN.det_polynomial(polynomial_matrix)

Determinant of a polynomial matrix in the z^{-1} convention.

Coefficients are ordered as [z^0, z^{-1}, z^{-2}, …] along axis 2. Uses an FFT-based approach: evaluate at DFT points, compute scalar det at each frequency, then IFFT back.

Parameters:

polynomial_matrix (ndarray) – shape (N, N, L), polynomial matrix entries.

Returns:

1-D array of determinant polynomial coefficients,

ordered [z^0, z^{-1}, …], trimmed to the actual degree.

Return type:

determinant