petsc-3.7.7 2017-09-25
Report Typos and Errors


Indicates the locations (rows and columns) in the matrix where nonzeros will be inserted using a local number of the rows and columns


#include <petscmat.h>
PetscErrorCode MatPreallocateSet(PetscInt nrows, PetscInt *rows,PetscInt ncols, PetscInt *cols,PetscInt *dnz, PetscInt *onz)
Not Collective

Input Parameters

row - the row
ncols - the number of columns in the matrix
cols - the columns indicated

Output Parameters

dnz - the array that will be passed to the matrix preallocation routines
ozn - the other array passed to the matrix preallocation routines


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 variables declared in MatPreallocateInitialize().

See Also

MatPreallocateFinalize(), MatPreallocateSet(), MatPreallocateSymmetricSetBlock(), MatPreallocateInitialize(),
MatPreallocateInitialize(), MatPreallocateSetLocal()

Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages