New user self-registration is currently disabled. Please email eigen-core-team @ lists.tuxfamily.org if you need an account.
Bug 918 - Add additional methods to control and access status results to UmfPackLU
Add additional methods to control and access status results to UmfPackLU
Status: RESOLVED FIXED
Product: Eigen
Classification: Unclassified
Component: Sparse
3.3 (current stable)
All All
: Normal Feature Request
Assigned To: Nobody
:
Depends on:
Blocks:
  Show dependency treegraph
 
Reported: 2014-12-15 00:22 UTC by João Rui Leal
Modified: 2015-11-27 21:06 UTC (History)
2 users (show)



Attachments
patch for UmfPackSupport.h (2.66 KB, patch)
2014-12-15 00:22 UTC, João Rui Leal
no flags Details | Diff

Description João Rui Leal 2014-12-15 00:22:18 UTC
Created attachment 507 [details]
patch for UmfPackSupport.h

UmfPackLU allows to perform factorizations where the matrix is singular, although this factorization cannot be used to solve linear systems, the LU factorization is still valid.

umfpack_numeric can return the status:
UMFPACK_WARNING_singular_matrix
Which is a successful factorization (from umfpack manual):
"UMFPACK_WARNING_singular_matrix: Numeric factorization was successful, but the matrix is singular"

It would be nice to access this return status so that the LU factorization could still be used. For instance, I would need this to use the LU factorization for a nullspace basis evaluation.

It would also be interesting to see/change the default settings of umfpack.

I have attached a patch that would add these features.
Comment 1 Gael Guennebaud 2015-11-27 21:06:36 UTC
Pushed after some minor renaming:

https://bitbucket.org/eigen/eigen/commits/1850206ae4e1/

Note You need to log in before you can comment on or make changes to this bug.