[Octave-bug-tracker] [bug #52402] Incorrect size of the solution of a singular system

[Marco Caliari]

URL:
  <http://savannah.gnu.org/bugs/?52402>

                 Summary: Incorrect size of the solution of a singular system
                 Project: GNU Octave
            Submitted by: caliari
            Submitted on: Tue 14 Nov 2017 08:42:37 AM UTC
                Category: Octave Function
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Incorrect Result
                  Status: Patch Submitted
             Assigned to: None
         Originator Name: 
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: dev
        Operating System: GNU/Linux

    _______________________________________________________

Details:

If you try


[Inf, 0;0, 0] \ [1; 1]


you get zeros (2) as a result. The problem is fixed by the attached patch. The
new result ([0; 0]) is consistent with


[realmax, 0;0, 0] \ [1; 1]
diag ([Inf, 0]) \ [1; 1]


and different from Matlab [0; Inf], but I think this is known.
In the function lssolve, I do not understand the need of the two variables
nrhs and b_nc. I think one in enough.




    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/bugs/?52402>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.gnu.org/