I noticed that numpy.linalg.solve has vastly different performance since v2.0.0, on both Linux and Windows (haven’t tested it on macOS). Basically, for reasonable matrices (up to about 1800×1800) the new versions are much faster (up to 10x faster of my Linux machine, I got even larger speedups on Windows), then for larger ones (up to about 8800×8800) the 1.26.4 version is faster, and for even larger ones the 2.0.0 version again becomes faster.

The following two functions logically do the same thing, but func2, which stores the result in a temporary variable, is slower.

I have a function that takes a 2 dimensional array, and returns an array of same shape that has a 1 if the value in the original array is next to (horizontally, vertically, or diagonally) a non-zero number, and 0 otherwise.