#include "petscmat.h" PetscErrorCode MatZeroRowsIS(Mat mat,IS is,PetscScalar diag,Vec x,Vec b)Collective on Mat Many br
mat | - the matrix Many br | |
is | - index set of rows to remove Many br | |
diag | - value put in all diagonals of eliminated rows Many br | |
x | - optional vector of solutions for zeroed rows (other entries in vector are not used) Many br | |
b | - optional vector of right hand side, that will be adjusted by provided solution Many br |
If the option MatSetOption(mat,MAT_KEEP_NONZERO_PATTERN,PETSC_TRUE) the nonzero structure Many brof the matrix is not changed (even for AIJ and BAIJ matrices) the values are Many brmerely zeroed. Many br
The user can set a value in the diagonal entry (or for the AIJ and Many brrow formats can optionally remove the main diagonal entry from the Many brnonzero structure as well, by passing 0.0 as the final argument). Many br
For the parallel case, all processes that share the matrix (i.e., Many brthose in the communicator used for matrix creation) MUST call this Many brroutine, regardless of whether any rows being zeroed are owned by Many brthem. Many br
Each processor can indicate any rows in the entire matrix to be zeroed (i.e. each process does NOT have to Many brlist only rows local to itself). Many br
You can call MatSetOption(mat,MAT_NO_OFF_PROC_ZERO_ROWS,PETSC_TRUE) if each process indicates only rows it Many browns that are to be zeroed. This saves a global synchronization in the implementation. Many br
Many br
Level:intermediate
Location:src/mat/interface/matrix.c
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages