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compute_fourier_basis Assertion Error

See original GitHub issue

I’m having trouble getting past assert self._e[-1] <= 2 with a graph when I try to compute its fourier basis, so I’m wondering in why this assertion would fail? Why does the largest eigenvalue have to be <= 2?

Issue Analytics

State:
Created 6 years ago
Reactions:2
Comments:7 (2 by maintainers)

Top GitHub Comments

2reactions

mdeffcommented, Jan 26, 2018

It’s indeed a numerical issue then (your largest eigenvalue is marginally above 2). We’ll relax the assertion. In the mean time you can just comment it. Thanks for reporting!

1reaction

nperraudcommented, Jan 18, 2018

This assertion is only done if the Laplacian is normalized.

if self.lap_type == 'normalized':
     # Spectrum bounded by [0, 2].
     assert self._e[-1] <= 2

In this case, the spectrum has to be bounded by 2 from the theory. So if your weight matrix is non-negative and symmetric, it should always pass this test.

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