The Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Math Forum » Discussions » Software » comp.soft-sys.matlab

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: Sparse integer LU decomposition
Replies: 6   Last Post: Dec 15, 2011 7:17 AM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Pascal Schulthess

Posts: 5
Registered: 12/8/11
Re: Sparse integer LU decomposition
Posted: Dec 8, 2011 11:57 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

"Steven_Lord" <> wrote in message <jbqp41$6n1$>...
> "Pascal Schulthess" <> wrote in
> message news:jbqof0$4bk$

> > Hi everyone,
> >
> > I was wondering if there is the possibility to perform sparse integer LU
> > decomposition preferably with full pivoting?
> >
> > I've tried to convert to intX and invoke lu(), but an error message is
> > displayed. I would really appreciate any help or hints concerning this.

> You can't have sparse integer type matrices in MATLAB.
> Even if you could, LU is not defined for integer types in MATLAB (the
> elements of the factors would likely be noninteger values.)
> What would you use this functionality to do if it were available? Perhaps
> there's an alternate way to achieve your goal using functionality that is
> available in MATLAB.
> --
> Steve Lord
> To contact Technical Support use the Contact Us link on

Ok, let me be a little more precise:

Not, I have a large sparse matrix and perform lu decomposition. Ideally, I'd like to convert this sparse matrix to integer and then perform lu. And if I would have three wishes, the resulting matrices would also be sparse and integer :)

But, ok, from you're answers I'm getting that this will not be possible. Perhaps I gotta look into UMFPACK be T. Davis or just ask him if he knows something :)

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.