Re: sparse matrix division (least squares)

[Rishi Amrit]

On Tue, Mar 31, 2009 at 12:14 AM, David Bateman <address@hidden> wrote:

Rishi Amrit wrote:

On Mon, Mar 30, 2009 at 6:02 PM, Ben Abbott <address@hidden <mailto:address@hidden>> wrote:


   On Mar 30, 2009, at 12:05 PM, Rishi Amrit wrote:

       Hi,

         I have two sparse matrices (say A and B).

       > size(A)
       ans =
         2400  2400

       > size(B)
       ans =
         2400 2440

       I wish to implement the least squares operator : A\B

       When I run this in MATLAB, I get

       > size(A\B)
       ans =
        2440  2400

       and A\B is a sparse matrix.

       When I implement this in octave, I get

       > A\B
       ans = Compressed Column Sparse (rows = 0, cols =0, nnz = 0)

       which is empty.

       Is there a separate function in octave for this operation on
       sparse matrices ?

       Thanks,

       Rishi


   What version of Octave are you running?


I am running the latest stable version: 3.0.3

Thanks,

Rishi

Where did you get your version of Octave? Is it built with SuiteSparse? I don't see this issue with 3.0.3 on my machine

Installing libsuitesparse-dev and recompiling octave fixed the issue.

Thanks,

Rishi