petsc-3.6.2 2015-10-02
   
MatPreallocateLocation
An alternative to MatPreallocationSet() that puts the nonzero locations into the matrix if it exists 
Synopsis
#include 
PetscErrorCode MatPreallocateLocations(Mat A,PetscInt row,PetscInt ncols,PetscInt *cols,PetscInt *dnz,PetscInt *onz)
Not Collective
Input Parameters
A  -matrix
row  -row where values exist (must be local to this process)
ncols  -number of columns
cols  -columns with nonzeros
dnz  -the array that will be passed to the matrix preallocation routines
ozn  -the other array passed to the matrix preallocation routines
Notes
See Users-Manual: Chapter 14 Hints for Performance Tuning for more details.
Do not malloc or free dnz and onz that is handled internally by these routines
This is a MACRO not a function because it uses a bunch of variables private to the MatPreallocation.... routines.
See Also
 MatPreallocateInitialize(), MatPreallocateSet(), MatPreallocateSymmetricSetBlock(), MatPreallocateSetLocal(),
MatPreallocateSymmetricSetLocalBlock()
Level:intermediate
Location:src/mat/../../include/petscmat.h
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages