Inverse of a sparse matrix could be dense, but what if I'm only interested in the main diagonal of the result? Is there a method that is more efficient than computing the full inverse?
Asked
Active
Viewed 2,143 times
3 Answers
2
You may be interested in work of Jok M. Tang and Yousef Saad. Their recent paper "Domain-decomposition-type methods for computing the diagonal of a matrix inverse" has the following abstract:

Jonas Meyer
- 53,602
-
The slides PEV linked to are by Saad, so there is some redundancy in our answers. – Jonas Meyer Jan 22 '11 at 03:35
-
I was hoping for something that I could quickly implement using standard linear algebra routines, I guess it's not possible – Yaroslav Bulatov Jan 23 '11 at 02:23
1
This(explanation of how to find diagonal of an inverse of a sparse matrix) should help.

NebulousReveal
- 13,935
1
We recently implemented in our solver PARDISO such as option where you can these results. The software is available at www.pardiso-project.org.
It is not yet documented in the manual b
Regards, Olaf

olaf schenk
- 21