[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Octave-bug-tracker] [bug #42418] luupdate transposes permutation matrix
From: |
David Spies |
Subject: |
[Octave-bug-tracker] [bug #42418] luupdate transposes permutation matrix if not constructed properly |
Date: |
Sat, 24 May 2014 19:15:06 +0000 |
User-agent: |
Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:29.0) Gecko/20100101 Firefox/29.0 |
URL:
<http://savannah.gnu.org/bugs/?42418>
Summary: luupdate transposes permutation matrix if not
constructed properly
Project: GNU Octave
Submitted by: dspyz
Submitted on: Sat 24 May 2014 07:15:05 PM GMT
Category: Octave Function
Severity: 3 - Normal
Priority: 5 - Normal
Item Group: Incorrect Result
Status: None
Assigned to: None
Originator Name:
Originator Email:
Open/Closed: Open
Discussion Lock: Any
Release: dev
Operating System: Any
_______________________________________________________
Details:
If the permutation matrix input is constructed as a column permutation, then
luupdate returns a different result than if constructed as a row permutation:
A = [0.091364 0.613038 0.999083;
0.594638 0.425302 0.603537;
0.383594 0.291238 0.085574;
0.265712 0.268003 0.238409;
0.669966 0.743851 0.445057 ];
u = [0.85082;
0.76426;
0.42883;
0.53010;
0.80683 ];
v = [0.98810;
0.24295;
0.43167 ];
[L,U,P1] = lu (A);
P2 = eye(5)(:,[2,3,5,4,1]);
P1 == P2 #True
[L,U,RP1] = luupdate (L,U,P1,u,v);
[L,U,RP2] = luupdate (L,U,P2,u,v);
RP1 == RP2 #False
_______________________________________________________
Reply to this item at:
<http://savannah.gnu.org/bugs/?42418>
_______________________________________________
Message sent via/by Savannah
http://savannah.gnu.org/
- [Octave-bug-tracker] [bug #42418] luupdate transposes permutation matrix if not constructed properly,
David Spies <=