[Octave-bug-tracker] [bug #60089] the sparse QR factorizion does not give economy sized Q

[Markus Mützel]

Update of bug #60089 (project octave):

                  Status:                    None => Fixed                  
             Open/Closed:                    Open => Closed                 
                 Release:                   4.2.2 => dev                    
        Operating System:               GNU/Linux => Any                    

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Follow-up Comment #1:

I can confirm that this is still an issue in Octave 6.2.0.

It seems to work as expected with a built from the development sources (which
will eventually become Octave 7):

>> Z = [magic(3); speye(3)];
>> [Q, ~] = qr(Z, 0);
>> size(Q)
ans =

   6   3

>> [Q, ~] = qr(full(Z), 0);
>> size(Q)
ans =

   6   3


This is probably because starting in that version Octave's `qr` function will
be using SPQR if available.

It is unlikely that that change will be backported to Octave 6 (because it
would be quite disruptive and break the API).

Closing as fixed for Octave 7.


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