clear (Data Acquisition Toolbox)

Remove device objects from the MATLAB workspace

Syntax

clear obj
clear obj.Channel(index)
clear obj.Line(index)

Arguments

obj
A device object or array of device objects.

obj.Channel(index)
One or more channels contained by obj.

obj.Line(index)
One or more lines contained by obj.

`obj`	A device object or array of device objects.
`obj.Channel(index)`	One or more channels contained by `obj`.
`obj.Line(index)`	One or more lines contained by `obj`.

Description

clear obj removes obj and all associated channels or lines from the MATLAB workspace, but not from the data acquisition engine.

clear obj.Channel(index) removes the specified channels contained by obj from the MATLAB workspace, but not from the data acquisition engine.

clear obj.Line(index) removes the specified lines contained by obj from the MATLAB workspace, but not from the data acquisition engine.

Remarks

Clearing device objects, channels, and lines follows these rules:

clear does not remove device objects, channels, or lines from the data acquisition engine. Use the delete function for this purpose.
If multiple references to a device object exist in the workspace, clearing one reference will not invalidate the remaining references.
You can restore cleared device objects to the MATLAB workspace with the daqfind function.

If you use the help command to display the M-file help for clear, then you must supply the pathname shown below.

```
help daq/private/clear
```

Example

Create the analog input object ai, copy ai to a new variable aicopy, and then clear the original device object from the MATLAB workspace.

ai = analoginput('winsound');
ch = addchannel(ai,1:2);
aicopy = ai;
clear ai

Retrieve ai from the engine with daqfind, and demonstrate that ai is identical to aicopy.

ainew = daqfind;
isequal(aicopy,ainew)
ans =
     1

See Also

Functions

daqfind, delete

binvec2dec daqcallback