Re: [petsc-users] Initializing a large sparse matrix

You have to preallocate, see https://petsc.org/release/docs/manual/mat/#sec-matsparse

El 17 oct 2022, a las 8:37, fujisan <[email protected]> escribió:

Hi everyone,

I initialize a large sparse matrix (50000x20000) using MatCreate() and then filling it with MatSetValues() line by line but it takes a bit more than an hour on 80 cores to fill in the matrix.

Is there a way to optimize this initialization?

Fuji