[Octave-bug-tracker] [bug #53589] Failing BIST test in bicg

[Marco Caliari]

Update of bug #53589 (project octave):

                  Status:             In Progress => Patch Submitted        

    _______________________________________________________

Follow-up Comment #4:

@Dmitri: yes, it is blas dependent. I see the problem only with openblas, not
with atlas or reference.

The problem is quite easy to solve, but there is a choice to make: in the code
there are a couple of denominators. The current code breaks with flag = 4 only
if the denominators are exactly zero. The other possibily would be to break if
the denominators are eps times smaller than the numerators (for instance). In
the first case, you may have false positive results (the code runs until max
number of iterations). In the second case, you may have false negative results
(the code breaks iterations that would have converged). From Matlab
documentation, it seems that the second approach is used. I attach a patch
which implements the second approach.

(file #43864)
    _______________________________________________________

Additional Item Attachment:

File name: bicg.m.diff                    Size:2 KB


    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/bugs/?53589>

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