Added is_finite check for 4x4 matrix inversion #1469
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Fixes #1432
The issue is related to multiplications where the result exceeds the maximum value for the underlying numeric representation. See the added tests for example matrices that pass the determinant check but yield infinite values in the inversion code.
Changes:
try_inversecorrectly returnsNonefor singular or near-singular matrices.reproducible_matrix).Notes:
is_finitecheck resulted in a 30% performance penalty (3ns instead of 2ns on my machine).InforNaNvalues.probablyalso affects 2x2 and 3x3 matrices.try_inverseto the method's documentation:Someis returned. Other definitions would require more involved threshold calculations to define a bound on result precision.