epfl-lts2 / pygsp

Graph Signal Processing in Python
https://pygsp.rtfd.io
BSD 3-Clause "New" or "Revised" License
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Filtering assumes Hermitian/symmetric Laplacian #106

Open iglesias opened 1 year ago

iglesias commented 1 year ago

compute_fourier_basis uses scipy.linalg.eigh assuming the matrix is complex Hermitian or real symmetric. This will lead to incorrect results, if I am not mistaken, when using for example the directed cycle graph (aka directed Ring or Path simple graph).

I am wondering if this is intended, for instance the library only supports filtering on non-directed graphs, or if there's anything else. Thank you in advance for any help!