Re: [petsc-users] petsc-users Digest, Vol 173, Issue 131

Range(snes->jacobian, , ); >> PetscInt row=1000, col=1000; >> PetscScalar v; >> if (row>=rstart && row> { >> MatGetValues(snes->jacobian, 1, , 1, , ); >> PetscPrintf(PETSC_COMM_WORLD, "rstart: %d, rend

Re: [petsc-users] Get global offset in global vector for the points not owned by this processor.

On Mon, May 29, 2023 at 5:47 PM YuSh Lo wrote: > Hi, > > How to get the offset in global vector for the points not owned by this > processor? > I have a parallel DMPlex and a section assigned to it. > GetSectionGetOffset with a global section returns -1 for the points not > owned by this

[petsc-users] Get global offset in global vector for the points not owned by this processor.

Hi, How to get the offset in global vector for the points not owned by this processor? I have a parallel DMPlex and a section assigned to it. GetSectionGetOffset with a global section returns -1 for the points not owned by this processor. Thanks, Josh

Re: [petsc-users] MatGetValues() can't return the correct values

Perhaps run a very small problem with 2 ranks and use MatView() to see the matrix before getting the values. Maybe use the debugger (-start_in_debugger) and step through the code as it gets values. I would say there is very little chance it is getting the "wrong values" and is more likely

[petsc-users] MatGetValues() can't return the correct values

/* Solve J Y = F, where J is Jacobian matrix */ ierr = SNESComputeJacobian(snes, X, snes->jacobian, snes->jacobian_pre); CHKERRQ(ierr); PetscInt rstart, rend; MatGetOwnershipRange(snes->jacobian, , ); PetscInt row=1000, col=1000; PetscScalar v; if (row>=rstart && rowjacobian, 1, , 1, , );