matrix SVD



Ruben Henner Zilibowitz wrote:
> I was wondering if there's a built in maxima function to compute the  
> SVD of a matrix (ie the Singular Value Decomposition). Is there one?

For a numerical SVD, there's dgesvd in the lapack contrib. 
Unfortunately, it's not documented at all.  But it looks like dgesvd(a, 
jobu, jobvt) will return a list containing the non-zero singular values, 
the left matrix U, and the transpose of the right matrix:  a = u*s*v^t.

If jobu is true, the matrix u is computed.  If jobvt is computed, v^t 
(transpose of v) is computed.

Ray