MatPreallocateSet#
Indicates the locations (rows and columns) in the matrix where nonzeros will be inserted using a local number of the rows and columns
Synopsis#
#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
onz - the other array passed to the matrix preallocation routines
(since v3.19)
Notes#
This routine is no longer needed since assembling matrices without explicit preallocation will not be slower than the use of this routine
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 MatPreallocateBegin().
See Also#
Matrices, MatPreallocateEnd(), MatPreallocateSet(), MatPreallocateSymmetricSetBlock()
MatPreallocateBegin(), MatPreallocateSetLocal()
Level#
deprecated
Location#
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages