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[Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix
From: |
Rik |
Subject: |
[Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix |
Date: |
Wed, 25 Nov 2020 16:38:48 -0500 (EST) |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.198 Safari/537.36 |
Update of bug #59488 (project octave):
Severity: 3 - Normal => 2 - Minor
Priority: 5 - Normal => 3 - Low
Release: 6.0.92 => dev
_______________________________________________________
Follow-up Comment #14:
Before a programmer can make use of eigenvalues and eigenvectors, they have to
have some understanding of the linear algebra involved. An all-zeros matrix
doesn't represent any useful linear transformation so it won't be encountered
in a practical case where a programmer is modeling a real-world phenomenon.
Maybe somebody doing something in pure math would have a zero-transform that
changes all inputs in a vector space in to the zero vector, but the pure math
folks don't need a numerical computation language for that, they can work this
out symbolically with pen and paper.
The all-zeros matrix is a corner case for which it would be nice to return a
value, rather than an error, but isn't critical to most Octave users.
But, I have noticed some issues with the documentation, input validation, and
naming conventions within eigs.m. I've got most of a changeset prepared which
fixes these items as well as handling the case of an all-zeros matrix. I plan
to check the code in on the development branch later today.
_______________________________________________________
Reply to this item at:
<https://savannah.gnu.org/bugs/?59488>
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- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, (continued)
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, Markus Mützel, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, JD, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, John W. Eaton, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, John W. Eaton, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, Rik, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, Rik, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, JD, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, John W. Eaton, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, Rik, 2020/11/20
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, JD, 2020/11/25
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix,
Rik <=
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, Rik, 2020/11/25
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, Rik, 2020/11/25
- [Octave-bug-tracker] [bug #59488] eigs error in dsaupd for zero matrix, Kai Torben Ohlhus, 2020/11/26