[Octave-bug-tracker] [bug #53140] Solution of a system of linear equations takes forever and hurts OS performance.

[Rik]

Follow-up Comment #9, bug #53140 (project octave):

I put in some debug statements and the slowdown is in this code which resizes
the matrix


                  std::cerr << "resizing sparse matrix" << std::endl;
                  for (octave_idx_type i = 0; i < b_nr; i++)
                    {
                      double tmp = Xx[i];
                      if (tmp != 0.0)
                        {
                          if (ii == x_nz)
                            {
                              // Resize the sparse matrix
                              octave_idx_type sz = x_nz * (b_nc - j) / b_nc;
                              sz = (sz > 10 ? sz : 10) + x_nz;
                              retval.change_capacity (sz);
                              x_nz = sz;
                            }
                          retval.xdata (ii) = tmp;
                          retval.xridx (ii++) = i;
                        }
                    }
                  std::cerr << "done resizing sparse matrix" << std::endl;





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