ISSetBlockSize#

informs an index set that it has a given block size

Synopsis#

#include "petscis.h" 
PetscErrorCode ISSetBlockSize(IS is, PetscInt bs)

Logicall Collective

Input Parameters#

  • is - index set

  • bs - block size

Notes#

This is much like the block size for Vecs. It indicates that one can think of the indices as being in a collection of equal size blocks. For ISBLOCK these collections of blocks are all contiguous within a block but this is not the case for other IS. For example, an IS with entries {0, 2, 3, 4, 6, 7} could have a block size of three set.

ISBlockGetIndices() only works for ISBLOCK, not others.

See Also#

IS, ISGetBlockSize(), ISCreateBlock(), ISBlockGetIndices(),

Level#

intermediate

Location#

src/vec/is/is/interface/index.c

Examples#

src/ksp/ksp/tutorials/ex73.c
src/ksp/ksp/tutorials/ex49.c
src/ksp/ksp/tutorials/ex76.c

Implementations#

ISSetBlockSize_Block() in src/vec/is/is/impls/block/block.c
ISSetBlockSize_General() in src/vec/is/is/impls/general/general.c
ISSetBlockSize_Stride() in src/vec/is/is/impls/stride/stride.c

Index of all IS routines
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Index of all manual pages