Hi all I want to check that the near nullspace I provide to GAMG gives "almost null vectors" when multiplying each vector in the near nullspace against the matrix problem.
This way I can check that the unknown ordering I am using is consistent, for example using by MatNullSpaceCreateRigidBody() or by computing the nullspace by myself. The thing is I do not know how I can get the nullspace object after calling PCSetCoordinates(). It gets a pointer to the PC object, but MatGetNearNullSpace() needs the matrix object. I assume at some point the matrix and the PC get linked, but when I ask MatGetNearNullSpace(matrix) passing the problem matrix after setting PCSetCoordinates(pc) I get: error: PETSc error 85-0 'Null Object: Parameter # 1' in /home/gtheler/libs/petsc-3.7.4/src/mat/interface/matnull.c MatNullSpaceGetVecs:64 thanks -- Jeremy Theler www.seamplex.com
