bugGNU Octave - Bugs: bug #34878, eigenvalue problems

 
 

bug #34878: eigenvalue problems

Submitted by:  kuo-wei <muslim>
Submitted on:  Tue 22 Nov 2011 01:00:27 PM UTC  
 
Category: LibrariesSeverity: 3 - Normal
Priority: 5 - NormalItem Group: Incorrect Result
Status: InvalidAssigned to: None
Originator Name: muslimOpen/Closed: Closed
Release: 3.2.4Operating System: GNU/Linux

Add a New Comment(Rich Markup)
   

You are not logged in

Please log in, so followups can be emailed to you.

 

Thu 16 Feb 2012 05:51:13 AM UTC, comment #1:

Sorry there was no response earlier but the volunteers who maintain Octave were in the middle of releasing version 3.6.0.

I think you would have better luck taking your example to the octave-help mailing list (http://www.gnu.org/software/octave/help.html).

Some of your questions relate to the difference between pure mathematics and numerical mathematics as practiced on computers. In particular, both null() and rank() use a tolerance to determine what qualifies as linearly dependent or independent. Use 'help null' and 'help rank' to see more.

Rik <rik5>
Project Administrator
Tue 22 Nov 2011 01:00:27 PM UTC, original submission:

Consider the above code, there are several problems
1. Executing this code many times(about 5~10) will generate two kinds of image results!
2. take a look at diag(d), the eigenvalue of B, there are no zero on the diagonal, but the null(B) is not empty, this is very strange.
3. Execute rank(v) and rank([v,F*v]) now, the answer will be 57 and 56, how can it be possible?

kuo-wei <muslim>

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attach File(s):
   
   
Comment:
   

No files currently attached

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -unavailable- added by rik5 (Posted a comment)
  • -unavailable- added by muslim (Submitted the item)
  • -unavailable- added by muslim
  •  

    Do you think this task is very important?
    If so, you can click here to add your encouragement to it.
    This task has 0 encouragements so far.

    Only project members can vote.

     

    Please enter the title of George Orwell's famous dystopian book (it's a date):

     

     

    Follow 3 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Thu 16 Feb 2012 05:51:13 AM UTCrik5StatusNone=>Invalid
      Open/ClosedOpen=>Closed
    Tue 22 Nov 2011 01:00:27 PM UTCmuslimCarbon-Copy-=>Added -unavailable-

    Back to the top


    Powered by Savane 3.1-cleanup1