In the end I went with "matrix_p = True" to ring like "permute_l" which was I think what you were suggesting anyways. Hopefully some day in the future we can change this to False and be done with it. On Sun, May 21, 2023 at 11:31 PM Andras Deak <deak.andris@gmail.com> wrote:
On Sun, May 21, 2023, at 17:08, Ilhan Polat wrote:
Sorry for reviving this thread, but indeed "p_indices" sounding uglier the more I look at it. Just to summarize what it does to save you from the thread above;
when
P, L, U = scipy.linalg.lu(A)
is run, currently, P is returning a full 2D array. If A is a tall array say, (25, 5) then P is necessarily (25, 25). And it is just a permutaiton matrix, a row shuffled np.eye(25). Instead, you can ask with this new keyword to return that shuffle pattern. as a 1D array and hence P becomes (25, ) array. And there are more than rare cases that only L and U is needed for other purposes.
So we would like to make that matrix vs array switch with a keyword. I thought "p_indices = True/False" was a good idea but it became a bit disturbing. Other matlab following software offers a string selector with "outputForm='matrix'/'vector'" which forces users to remember the options hence I am voting for a TrueFalse flag. However I can't come up with the right keyword.
Could you please offer some alternatives even just for inspiration?
How about reversing the meaning of the flag and naming it something like `p_full` or `full_p` with a `True` default? I also considered "squareform" instead of "full" as in `spatial.distance.squareform`, because there's a similar 1d <-> 2d square thing here, but the semantics are different enough that this name would probably be more confusing than helpful.
András
Best, ilhan
On Tue, Apr 25, 2023 at 9:34 AM Jake Bowhay <jb9.bowhay@gmail.com>
wrote:
It would be nice to add a quick note to the docs explaining when/which you should use. Currently both state "Compute pivoted LU decomposition of a matrix." which while true isn't very helpful for a user trying to decide which function to pick! _______________________________________________ SciPy-Dev mailing list -- scipy-dev@python.org To unsubscribe send an email to scipy-dev-leave@python.org https://mail.python.org/mailman3/lists/scipy-dev.python.org/ Member address: ilhanpolat@gmail.com
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