tolerance for diagonal entries + Slepc

Hong Zhang hzhang at
Mon Aug 3 09:13:31 CDT 2009

The error msg
"Matrix is missing diagonal entry 1847!"
has nothing to do with the tolerance.
It indicates that you did not input any value
to the 1847-th diagonal entry.
Many routines required diagonal entries been
allocated and set.
If that entry is zero, you should set zero value to it.


On Mon, 3 Aug 2009, Umut Tabak wrote:

> Umut Tabak wrote:
>> Dear all,
>> I am reading some matrices into petsc, but some of the diagonal entries are 
>> really small, on the order of e-8. Petsc complains about missing diagonal 
>> entries, I guess it compares them with some predefined tolerance value, is 
>> there a way to change/set these tolerances?
>> Error is "Matrix is missing diagonal entry 1847!" after read from a matrix 
>> market formatted text file.
>> Best regards,
>> Umut
> sorry that I forgot to explain my problem completely, I get this error when I 
> try to use Slepc's EPSSolve function, so that the question is also related to 
> Slepc I guess. I mean the tolerancing issues for the matrices.

More information about the petsc-users mailing list