:orphan:
# PetscOptionsEList
Puts a list of option values that a single one may be selected from 
## Synopsis
```
#include "petscsys.h"
PetscErrorCode  PetscOptionsEList(const char opt[],const char ltext[],const char man[],const char *const *list,PetscInt ntext,const char currentvalue[],PetscInt *value,PetscBool  *set)
```
Logically Collective on the communicator passed in `PetscOptionsBegin()`


## Input Parameters

- ***opt -*** option name
- ***ltext -*** short string that describes the option
- ***man -*** manual page with additional information on option
- ***list -*** the possible choices (one of these must be selected, anything else is invalid)
- ***ntext -*** number of choices
- ***currentvalue -*** the current value; caller is responsible for setting this value correctly. Normally this is done with


```none
                 PetscOptionsEList(..., obj->value,&value,&flg);
```



## Output Parameters

- ***value -*** the index of the value to return
- ***set -*** `PETSC_TRUE` if found, else `PETSC_FALSE`





## Notes
Must be between a `PetscOptionsBegin()` and a `PetscOptionsEnd()`

If the user does not supply the option at all `value` is NOT changed. Thus
you should ALWAYS initialize `value` if you access it without first checking if the `set` flag is `PETSC_TRUE`.

See `PetscOptionsFList()` for when the choices are given in a `PetscFunctionList()`


## See Also
 `PetscOptionsGetInt()`, `PetscOptionsGetReal()`,
`PetscOptionsHasName()`, `PetscOptionsGetIntArray()`, `PetscOptionsGetRealArray()`, `PetscOptionsBool()`,
`PetscOptionsName()`, `PetscOptionsBegin()`, `PetscOptionsEnd()`, `PetscOptionsHeadBegin()`,
`PetscOptionsStringArray()`, `PetscOptionsRealArray()`, `PetscOptionsScalar()`,
`PetscOptionsBoolGroupBegin()`, `PetscOptionsBoolGroup()`, `PetscOptionsBoolGroupEnd()`,
`PetscOptionsFList()`, `PetscOptionsEnum()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/objects/aoptions.c.html#PetscOptionsEList">src/sys/objects/aoptions.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex29.c.html">src/ksp/ksp/tutorials/ex29.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex32.c.html">src/ksp/ksp/tutorials/ex32.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex35.cxx.html">src/ksp/ksp/tutorials/ex35.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex36.cxx.html">src/ksp/ksp/tutorials/ex36.cxx</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex71.c.html">src/ksp/ksp/tutorials/ex71.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex73.c.html">src/ksp/ksp/tutorials/ex73.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex12.c.html">src/snes/tutorials/ex12.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex17.c.html">src/snes/tutorials/ex17.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex36.c.html">src/snes/tutorials/ex36.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex62.c.html">src/snes/tutorials/ex62.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex63.c.html">src/snes/tutorials/ex63.c</A><BR>


---
[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/sys/objects/aoptions.c)


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