:orphan:
# MatOption
Options that may be set for a matrix that indicate properties of the matrix or affect its behavior or storage 
## Synopsis
```
typedef enum {
  MAT_OPTION_MIN                  = -3,
  MAT_UNUSED_NONZERO_LOCATION_ERR = -2,
  MAT_ROW_ORIENTED                = -1,
  MAT_SYMMETRIC                   = 1,
  MAT_STRUCTURALLY_SYMMETRIC      = 2,
  MAT_FORCE_DIAGONAL_ENTRIES      = 3,
  MAT_IGNORE_OFF_PROC_ENTRIES     = 4,
  MAT_USE_HASH_TABLE              = 5,
  MAT_KEEP_NONZERO_PATTERN        = 6,
  MAT_IGNORE_ZERO_ENTRIES         = 7,
  MAT_USE_INODES                  = 8,
  MAT_HERMITIAN                   = 9,
  MAT_SYMMETRY_ETERNAL            = 10,
  MAT_NEW_NONZERO_LOCATION_ERR    = 11,
  MAT_IGNORE_LOWER_TRIANGULAR     = 12,
  MAT_ERROR_LOWER_TRIANGULAR      = 13,
  MAT_GETROW_UPPERTRIANGULAR      = 14,
  MAT_SPD                         = 15,
  MAT_NO_OFF_PROC_ZERO_ROWS       = 16,
  MAT_NO_OFF_PROC_ENTRIES         = 17,
  MAT_NEW_NONZERO_LOCATIONS       = 18,
  MAT_NEW_NONZERO_ALLOCATION_ERR  = 19,
  MAT_SUBSET_OFF_PROC_ENTRIES     = 20,
  MAT_SUBMAT_SINGLEIS             = 21,
  MAT_STRUCTURE_ONLY              = 22,
  MAT_SORTED_FULL                 = 23,
  MAT_FORM_EXPLICIT_TRANSPOSE     = 24,
  MAT_STRUCTURAL_SYMMETRY_ETERNAL = 25,
  MAT_SPD_ETERNAL                 = 26,
  MAT_OPTION_MAX                  = 27
} MatOption;
```



## Note
See `MatSetOption()` for the use of the options


## Developer Note
Entries that are negative need not be called collectively by all processes.


## See Also
 [](ch_matrices), `Mat`, `MatSetOption()`

## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscmat.h.html#MatOption">include/petscmat.h</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex18.c.html">src/ksp/ksp/tutorials/ex18.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex19.c.html">src/ksp/ksp/tutorials/ex19.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex2.c.html">src/ksp/ksp/tutorials/ex2.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex21.c.html">src/ksp/ksp/tutorials/ex21.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex4.c.html">src/ksp/ksp/tutorials/ex4.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex5.c.html">src/ksp/ksp/tutorials/ex5.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex52.c.html">src/ksp/ksp/tutorials/ex52.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex54.c.html">src/ksp/ksp/tutorials/ex54.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex54f.F90.html">src/ksp/ksp/tutorials/ex54f.F90</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex55.c.html">src/ksp/ksp/tutorials/ex55.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex56.c.html">src/ksp/ksp/tutorials/ex56.c</A><BR>


---
[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/include/petscmat.h)


[Index of all Mat routines](index.md)  
[Table of Contents for all manual pages](/manualpages/index.md)  
[Index of all manual pages](/manualpages/singleindex.md)