PCMGMatResidualTransposeDefault#
Default routine to calculate the residual of the transposed linear system
Synopsis#
#include "petscksp.h"
PetscErrorCode PCMGMatResidualTransposeDefault(Mat mat, Mat b, Mat x, Mat r)
Collective
Input Parameters#
mat - the matrix
b - the right-hand side
x - the approximate solution
Output Parameter#
r - location to store the residual
Note#
When r is dense, the MatProduct computing it stays attached to r, so that later calls with the same mat and nonzero pattern only run
its numeric phase; it keeps references to mat and x until MatProductClear() is called on r or r is destroyed.
See Also#
KSP: Linear System Solvers, PCMG, PCMGSetMatResidualTranspose()
Level#
developer
Location#
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages