# TSEquationType
type of `TS` problem that is solved 
## Synopsis
```
typedef enum {
  TS_EQ_UNSPECIFIED               = -1,
  TS_EQ_EXPLICIT                  = 0,
  TS_EQ_ODE_EXPLICIT              = 1,
  TS_EQ_DAE_SEMI_EXPLICIT_INDEX1  = 100,
  TS_EQ_DAE_SEMI_EXPLICIT_INDEX2  = 200,
  TS_EQ_DAE_SEMI_EXPLICIT_INDEX3  = 300,
  TS_EQ_DAE_SEMI_EXPLICIT_INDEXHI = 500,
  TS_EQ_IMPLICIT                  = 1000,
  TS_EQ_ODE_IMPLICIT              = 1001,
  TS_EQ_DAE_IMPLICIT_INDEX1       = 1100,
  TS_EQ_DAE_IMPLICIT_INDEX2       = 1200,
  TS_EQ_DAE_IMPLICIT_INDEX3       = 1300,
  TS_EQ_DAE_IMPLICIT_INDEXHI      = 1500
} TSEquationType;
```



## Developer Notes
this must match petsc/finclude/petscts.h


## Supported types are
`TS_EQ_UNSPECIFIED` (default)
`TS_EQ_EXPLICIT` {ODE and DAE index 1, 2, 3, HI}: F(t,U,U_t) := M(t) U_t - G(U,t) = 0
`TS_EQ_IMPLICIT` {ODE and DAE index 1, 2, 3, HI}: F(t,U,U_t) = 0


## See Also
 `TSGetEquationType()`, `TSSetEquationType()`

## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscts.h.html#TSEquationType">include/petscts.h</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex20adj.c.html">src/ts/tutorials/ex20adj.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex20opt_ic.c.html">src/ts/tutorials/ex20opt_ic.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex20opt_p.c.html">src/ts/tutorials/ex20opt_p.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex20td.c.html">src/ts/tutorials/ex20td.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex25.c.html">src/ts/tutorials/ex25.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex35.cxx.html">src/ts/tutorials/ex35.cxx.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex36.c.html">src/ts/tutorials/ex36.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex36A.c.html">src/ts/tutorials/ex36A.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex36SE.c.html">src/ts/tutorials/ex36SE.c.html</A><BR>


---
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