[SciPy-user] problem using umfpack.lu()

Giampaolo Cuoghi jpaul74@gmail....
Sun Dec 21 16:00:57 CST 2008


Nathan Bell <wnbell <at> gmail.com> writes:

> 
> On Sat, Dec 20, 2008 at 1:03 PM, Giampaolo Cuoghi <jpaul74 
<at> gmail.com> wrote:
> >
> > I'm trying to solve the problem of compute the determinant of a sparse
> > matrix, as I've written in the previous mail.
> >
> > I find that the LU decomposition can be useful for this task but when I
> > use umfpack.lu(A) for A complex sparse matrix, this error appears:
> >
> > "matrix must have float64 values"
> >
> > If A is a real matrix no error appears.
> >
> > Can someone help me?
> >
> 
> Giampaolo, you should convert A to the float64 type first:
> 
> umfpack.lu(A.astype('float64'))
> 

Thanks Nathan, but my matrix A is complex so with A.astype('float64') the
imaginary part disappear and if I use A.astype('complex64') or
A.astype('complex128') the previous error appears: "matrix must have 
float64 values". It seems that the lu decomposition doesn't work for 
complex matrix.




More information about the SciPy-user mailing list