# TSSetMatStructure
sets the relationship between the nonzero structure of the RHS Jacobian matrix to the IJacobian matrix. 
## Synopsis
```
#include "petscts.h"  
PetscErrorCode TSSetMatStructure(TS ts, MatStructure str)
```
Logically  Collective


## Input Parameters

- ***ts -*** the time-stepper
- ***str -*** the structure (the default is `UNKNOWN_NONZERO_PATTERN`)





## Note
When the relationship between the nonzero structures is known and supplied the solution process can be much faster


## See Also
 [](chapter_ts), `TS`, `MatAXPY()`, `MatStructure`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/interface/ts.c.html#TSSetMatStructure">src/ts/interface/ts.c</A>


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[Index of all TS routines](index.md)  
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