# MATSEQAIJ#

MATSEQAIJ = “seqaij” - A matrix type to be used for sequential sparse matrices, based on compressed sparse row format.

## Options Database Keys#

• -mat_type seqaij - sets the matrix type to “seqaij” during a call to MatSetFromOptions()

## Notes#

MatSetValues() may be called for this matrix type with a NULL argument for the numerical values, in this case the values associated with the rows and columns one passes in are set to zero in the matrix

MatSetOptions(,MAT_STRUCTURE_ONLY,PETSC_TRUE) may be called for this matrix type. In this no space is allocated for the nonzero entries and any entries passed with MatSetValues() are ignored

## Developer Note#

It would be nice if all matrix formats supported passing NULL in for the numerical values

## See Also#

MatCreateSeqAIJ(), MatSetFromOptions(), MatSetType(), MatCreate(), MatType, MATSELL, MATSEQSELL, MATMPISELL

beginner

## Location#

src/mat/impls/aij/seq/aij.c

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