:orphan:
# MatProductSetType
Sets a particular matrix-matrix product operation to be used to compute the values of the given matrix
## Synopsis
```
#include "petscmat.h"
PetscErrorCode MatProductSetType(Mat mat, MatProductType productype)
```
Collective
## Input Parameters
- ***mat -*** the matrix whose values are computed via a matrix-matrix product operation
- ***productype -*** matrix product type, e.g., `MATPRODUCT_AB`,`MATPRODUCT_AtB`,`MATPRODUCT_ABt`,`MATPRODUCT_PtAP`,`MATPRODUCT_RARt`,`MATPRODUCT_ABC`,
see `MatProductType`
## Note
The small t represents the transpose operation.
## See Also
[](ch_matrices), `MatProduct`, `Mat`, `MatProductCreate()`, `MatProductType`, `MatProductType`,
`MATPRODUCT_AB`, `MATPRODUCT_AtB`, `MATPRODUCT_ABt`, `MATPRODUCT_PtAP`, `MATPRODUCT_RARt`, `MATPRODUCT_ABC`
## Level
intermediate
## Location
src/mat/interface/matproduct.c
## Examples
src/tao/pde_constrained/tutorials/parabolic.c
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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/mat/interface/matproduct.c)
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