# warning

Display a warning message.

## Syntax

* warning()
* warning(msg)
* warning(id, msg)
* warning(state)
* warning(state, id)
* st = warning()
* warning(st)

## Input argument

* id - a string: identifier for the warning.
* msg - a string: message to warn.
* state - a string: 'on', 'off', 'aserror', 'all' or 'query'.
* st - a struct: set warning settings.

## Output argument

* st - a struct, warning settings.

## Description

**warning** displays a warning message.

**warning('')** resets lastwarn state.

## Examples

```matlab
warning('your warning message.')
```

```matlab
warning('on', 'myModule:identifier');
warning('myModule:identifier', 'my message 1 on');
warning('off', 'myModule:identifier');
warning('myModule:identifier', 'my message 2 off');
warning('aserror', 'myModule:identifier');
warning('myModule:identifier', 'my message 3 as error');
```

## See also

[lasterror](lasterror), [error](error), [lastwarn](lastwarn).

## History

| Version | Description     |
| ------- | --------------- |
| 1.0.0   | initial version |

## Author

Allan CORNET
