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


## Input Parameters

- ***opt -*** option name
- ***text -*** short string that describes the option
- ***man -*** manual page with additional information on option
- ***list -*** the possible choices
- ***currentvalue -*** the current value; caller is responsible for setting this value correctly. Normally this is done with

```none
                 PetscOptionsFlist(..., obj->value,value,len,&flg);
                 if (flg) {
```

- ***len -*** the length of the character array value



## Output Parameters

- ***value -*** 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`.

The `currentvalue` passed into this routine does not get transferred to the output `value` variable automatically.

See `PetscOptionsEList()` for when the choices are given in a string array

To get a listing of all currently specified options,
see `PetscOptionsView()` or `PetscOptionsGetAll()`


## Developer Note
This cannot check for invalid selection because of things like `MATAIJ` that are not included in the list


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

## Level
intermediate

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

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/field/tutorials/ex1.c.html">src/dm/field/tutorials/ex1.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex10.c.html">src/ksp/ksp/tutorials/ex10.c</A><BR>
<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/ex74.c.html">src/ksp/ksp/tutorials/ex74.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex76.c.html">src/ksp/ksp/tutorials/ex76.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex77.c.html">src/ksp/ksp/tutorials/ex77.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/ex48.c.html">src/snes/tutorials/ex48.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex11.c.html">src/ts/tutorials/ex11.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex11_sa.c.html">src/ts/tutorials/ex11_sa.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)