[petsc-users] SLEPc EPS Tolerance

[Eda Oktay]

> How do you measure accuracy?
Using the word accuracy may be not true actually, I am sorry. I am
using eigenvectors corresponding to these eigenvalues in k-means
algorithm, then do spectral graph partitioning. I must look at the
partition quality. By quality, I mean, the resulting edge cut of my
partitioned graph. I thought that the less tolerance results in more
accuracy, hence more qualified partition.

> What do you mean "the result was still the same"?
I mean I am still not getting the most qualified solution in E-10,
still E-2 or E-6 gives more qualified partitions, i.e. they give less
edge cut.

>What is the eigenvalue you are computing?
I am computing the smallest eigenvalue of a Laplacian matrix.