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[Lapack] issue with DGGSVD in LAPACK


I am just trying to divert the problem but
why don't you use mkl to start with?
or at least ifort and fortran lapack?

I understand that there is a problem with icc and clapack though.


On Wed, 8 Jul 2009, Eric Loomis wrote:

Hello, I ran into a problem building the LAPACK (c version) on a high
performance computing platform using an icc compiler.  The libraries
seemed to build okay, but when I ran the testing executables I ran
into some errors in the SVD routine.  I have attached the output file
with the errors.  Do you know what may have caused these errors?

I have probably a related problem when I try to run some of my code
using the DGESVD routine in that I get an error
** On entry to DGESVD, parameter number  4 had an illegal value

 INFO = -4
 LWORK = -1

Can you help me with any of these issues?

thanks.

At 10:21 AM -0700 6/25/09, Zhaojun Bai wrote:
Hi Eric,

I would be happy to try to help out here. Can you let me
the exact formulation of the constrained LS
problem you want to solver? I can take a look and
see whether we're on the right-track to use the DGGSVD
from LAPACK.

Apologize the delay for response. We just finished the spring
quarter term.

Regards,
Zhaojun Bai
UC Davis




Eric Loomis wrote:
Hello,

I am using the routine DGGSVD (CLAPACK) to solve constrained least
squares problems.  To do this I need to form a matrix X from Q and
R as discussed in GSVD literature.  R appears to be nearly
diagonal. The result of using the GSVD to solve a system of
equations is that the first half of the solution is nearly zero,
but the second half gives the correct answer.  Can you put me in
contact with someone familiar with this routine to work out this
issue?  I can supply the source code if required.



-- 
Eric Loomis
P-24 plasma physics
Los Alamos National Laboratory
mailstop E526
505-665-3196
loomis@Domain.Removed

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