propinfo (Data Acquisition Toolbox)

Return property characteristics for device objects, channels, or lines

Syntax

out = propinfo(obj)
out = propinfo(obj,'PropertyName')

Arguments

obj
A device object, channels, or lines.

'PropertyName'
A valid obj property name.

out
A structure whose field names are the property names for obj (if PropertyName is not specified).

`obj`	A device object, channels, or lines.
`'PropertyName'`	A valid `obj` property name.
`out`	A structure whose field names are the property names for `obj` (if `PropertyName` is not specified).

Description

out = propinfo(obj) returns the structure out whose field names are the property names for obj. Each property name in out contains the fields shown below.

Field Name
Description

Type
The property data type. Possible values are any, callback, double, and string.

Constraint
The type of constraint on the property value. Possible values are bounded, callback, enum, and none.

ConstraintValue
The property value constraint. The constraint can be a range of valid values or a list of valid string values.

DefaultValue
The property default value.

ReadOnly
If the property is read-only, a 1 is returned. Otherwise, a 0 is returned.

ReadOnlyRunning
If the property is read-only while the device object is running, a 1 is returned. Otherwise, a 0 is returned.

DeviceSpecific
If the property is device-specific, a 1 is returned. If a 0 is returned, the property is supported for all device objects of a given type.

Field Name	Description
`Type`	The property data type. Possible values are `any`, `callback`, `double`, and `string`.
`Constraint`	The type of constraint on the property value. Possible values are `bounded`, `callback`, `enum`, and `none`.
`ConstraintValue`	The property value constraint. The constraint can be a range of valid values or a list of valid string values.
`DefaultValue`	The property default value.
`ReadOnly`	If the property is read-only, a 1 is returned. Otherwise, a 0 is returned.
`ReadOnlyRunning`	If the property is read-only while the device object is running, a 1 is returned. Otherwise, a 0 is returned.
`DeviceSpecific`	If the property is device-specific, a 1 is returned. If a 0 is returned, the property is supported for all device objects of a given type.

out = propinfo(obj,'PropertyName') returns the structure out for the property specified by PropertyName. If PropertyName is a cell array of strings, a cell array of structures is returned for each property.

Example

Create the analog input object ai for a sound card and configure it to operate in stereo mode.

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

To capture all property information for all common ai properties:

```
out = propinfo(ai);
```

To display the default value for the SampleRate property:

out.SampleRate.DefaultValue
ans =
        8000

To display all the property information for the InputRange property:

propinfo(ai.Channel,'InputRange')
ans = 
               Type: 'double'
         Constraint: 'Bounded'
    ConstraintValue: [-1 1]
       DefaultValue: [-1 1]
           ReadOnly: 0
    ReadOnlyRunning: 1
     DeviceSpecific: 0

See Also

Functions

daqhelp

peekdata putdata