petsc-3.7.1 2016-05-15
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MatPreallocateLocation

An alternative to MatPreallocationSet() that puts the nonzero locations into the matrix if it exists

Synopsis

#include <petscmat.h>
PetscErrorCode MatPreallocateLocations(Mat A,PetscInt row,PetscInt ncols,PetscInt *cols,PetscInt *dnz,PetscInt *onz)
Not Collective Many br

Input Parameters

A -matrix Many br
row -row where values exist (must be local to this process) Many br
ncols -number of columns Many br
cols -columns with nonzeros Many br
dnz -the array that will be passed to the matrix preallocation routines Many br
ozn -the other array passed to the matrix preallocation routines Many br

Many br

Notes

See Users-Manual: Chapter 14 Hints for Performance Tuning for more details. Many br

Do not malloc or free dnz and onz that is handled internally by these routines Many br

This is a MACRO not a function because it uses a bunch of variables private to the MatPreallocation.... routines. Many br

See Also

MatPreallocateInitialize(), MatPreallocateSet(), MatPreallocateSymmetricSetBlock(), MatPreallocateSetLocal(),
MatPreallocateSymmetricSetLocalBlock() Many br

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