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

[anonymous]

URL:
  <http://savannah.gnu.org/bugs/?53140>

                 Summary: Solution of a system of linear equations takes
forever and hurts OS performance.
                 Project: GNU Octave
            Submitted by: None
            Submitted on: Tue 13 Feb 2018 10:48:10 AM UTC
                Category: Performance
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Performance
                  Status: None
             Assigned to: None
         Originator Name: Octave user
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: 4.2.1
        Operating System: Microsoft Windows

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Details:

The execution of the following code takes at least ten hours or more.

clear all;
close all;

load linsolve_test.mat;

tic;
x = A \ b;
toc;

However the LU decomposition of A takes only a few seconds:

tic;
[L, U, P, Q, R] = lu (A);
x = Q * ( U \ ( L \ ( P * ( R \ b ) ) ) );
toc;



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File Attachments:


-------------------------------------------------------
Date: Tue 13 Feb 2018 10:48:10 AM UTC  Name: linsolve_test.7z  Size: 1MiB  
By: None

<http://savannah.gnu.org/bugs/download.php?file_id=43269>

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  <http://savannah.gnu.org/bugs/?53140>

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