pyFDN.fdn_matrix_gallery

pyFDN.fdn_matrix_gallery(N=None, matrix_type=None, *, angles=None, kernel_type='rotation')

Return a feedback matrix of the requested type, or list all type names.

Parameters:

• N (int | None) – Matrix size. Ignored when matrix_type is None.

• matrix_type (str | None) – One of the supported type strings. Pass None (or call with no arguments) to get the list of all type names.

• angles (ArrayLike | None) – Kernel angles for the "kronecker" type, innermost first (see pyFDN.kronecker_matrix()). Defaults to pi / 4 on every kernel, the equal-mixing setting. Ignored otherwise.

• kernel_type (str | Sequence[str]) – Kernel family for the "kronecker" type, "rotation" or "reflection", either once for all kernels or one per kernel. Ignored otherwise.

Return type:

ndarray | list[str]

Returns:

Feedback matrix of shape (N, N), or a list of type-name strings.

Example:

fdn_matrix_gallery()             # → list of type strings
fdn_matrix_gallery(4, "orthogonal")
fdn_matrix_gallery(8, "hadamard")
fdn_matrix_gallery(8, "kronecker", angles=[0.0, np.pi / 4, np.pi / 8])