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[Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorizat
From: |
Marco Caliari |
Subject: |
[Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorization |
Date: |
Wed, 6 Sep 2017 12:13:25 -0400 (EDT) |
User-agent: |
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:55.0) Gecko/20100101 Firefox/55.0 |
Follow-up Comment #3, bug #51950 (project octave):
I confirm the problem in 4.2.1. It seems to me that in order to trigger the
bug you need r rectangular and with some zeros on the diagonal. I have no
problem with
A = sprandn(5, 6, 1);[q r] = qr(A);[q r] = qr(r);
(no zeros on the diagonal of r) or
A = sprandn(5, 5, 0.1);[q r] = qr(A);[q r] = qr(r);
(r is square). But, it is strange to me that I have no problem with
r = sprandn(5, 6, 0.1);r = triu(r);[q r] = qr(r);
It seems that r has to be the result of a qr factorization and not a simple
upper triangular rectangular matrix with some zeros on the diagonal. Strange.
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- [Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorization, Joseph Young, 2017/09/05
- [Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorization, Doug Stewart, 2017/09/05
- [Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorization, Dmitri A. Sergatskov, 2017/09/05
- [Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorization,
Marco Caliari <=
- [Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorization, Mike Miller, 2017/09/06
- [Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorization, Mike Miller, 2017/09/06
- [Octave-bug-tracker] [bug #51950] Segfault during a sparse QR factorization, Mike Miller, 2017/09/06
- [Octave-bug-tracker] [bug #51950] sparse qr may return a malformed sparse matrix R with out of bounds entries, Mike Miller, 2017/09/06
- [Octave-bug-tracker] [bug #51950] sparse qr may return a malformed sparse matrix R with out of bounds entries, Marco Caliari, 2017/09/06
- [Octave-bug-tracker] [bug #51950] sparse qr may return a malformed sparse matrix R with out of bounds entries, Rik, 2017/09/06
- [Octave-bug-tracker] [bug #51950] sparse qr may return a malformed sparse matrix R with out of bounds entries, Rik, 2017/09/06
- [Octave-bug-tracker] [bug #51950] sparse qr may return a malformed sparse matrix R with out of bounds entries, Rik, 2017/09/06
- [Octave-bug-tracker] [bug #51950] sparse qr may return a malformed sparse matrix R with out of bounds entries, Dmitri A. Sergatskov, 2017/09/07
- [Octave-bug-tracker] [bug #51950] sparse qr may return a malformed sparse matrix R with out of bounds entries, Joseph Young, 2017/09/07