MatStashSetInitialSize — PETSc 3.25.2 documentation

Skip to main content
`Ctrl`+`K`

# MatStashSetInitialSize

sets the sizes of the matrix stash, that is used during the assembly process to store values that belong to other processors.

## Synopsis

    #include "petscmat.h"
    PetscErrorCode MatStashSetInitialSize(Mat mat, PetscInt size, PetscInt bsize)

Not Collective

## Input Parameters

- mat - the matrix

- size - the initial size of the stash.

- bsize - the initial size of the block-stash(if used).

## Options Database Keys

- -matstash_initial_size size or size0,size1,…,sizep- 1 - set initial size

- -matstash_block_initial_size bsize or bsize0,bsize1,…,bsizep- 1 - set initial block size

## Notes

The block-stash is used for values set with `MatSetValuesBlocked()` while the stash is used for values set with `MatSetValues()`

Run with the option -info and look for output of the form MatAssemblyBegin_MPIXXX:Stash has MM entries, uses nn mallocs. to determine the appropriate value, MM, to use for size and MatAssemblyBegin_MPIXXX:Block-Stash has BMM entries, uses nn mallocs. to determine the value, BMM to use for bsize

## See Also

Matrices, `MatAssemblyBegin()`, `MatAssemblyEnd()`, `Mat`, `MatStashGetInfo()`

## Level

intermediate

## Location

src/mat/interface/matrix.c

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