It seems that LAPACK becomes unstable on ARM when attempting to find the eigenvectors and eigenvalues of a diagonal matrix. This instability is triggered in find-diagonalizer-in-e-basis. The operation becomes trivial when run on a diagonal matrix, so we check for this and return the identity to avoid making a potentially unstable LAPACK call.
notmgsk
commented
1 year ago
It seems that LAPACK becomes unstable on ARM when attempting to find the eigenvectors and eigenvalues of a diagonal matrix. This instability is triggered in find-diagonalizer-in-e-basis. The operation becomes trivial when run on a diagonal matrix, so we check for this and return the identity to avoid making a potentially unstable LAPACK call.
Fixes #842.