instrfindall - Find visible and hidden instrument objects

Syntax

Arguments

'P1'	Name of an instrument object property or device group object property
V1	Value allowed for corresponding P1.
s	A structure of property names and property values.
objs	An array of instrument objects or device group objects.
out	An array of returned instrument objects or device group objects.

Description

out = instrfindall finds all instrument objects and device group objects, regardless of the value of the objects' ObjectVisibility property. The object or objects are returned to out.

out = instrfindall('P1',V1,...) returns an array, out, of instrument objects and device group objects whose property names and corresponding property values match those specified as arguments.

out = instrfindall(s) returns an array, out, of instrument objects whose property names and corresponding property values match those specified in the structure s, where the field names correspond to property names and the field values correspond to the current value of the respective property.

out = instrfindall(objs,'P1',V1,...) restricts the search for objects with matching property name/value pairs to the instrument objects and device group objects listed in objs.

Note that you can use string property name/property value pairs, structures, and cell array property name/property value pairs in the same call to instrfindall.

Tips

instrfindall differs from instrfind in that it finds objects whose ObjectVisibility property is set to off.

Property values are case sensitive. You must specify property values using the same format as that returned by the get function. For example, if get returns the Name property value as MyObject, instrfindall will not find an object with a Name property value of myobject. However, this is not the case for properties that have a finite set of string values.

For example, instrfindall will find an object with a Parity property value of Even or even. You can use the propinfo function to determine if a property has a finite set of string values.

Examples

Suppose you create the following instrument objects on a Windows machine.

s1 = serial('COM1');
s2 = serial('COM2');
g1 = gpib('keithley',0,2);
set(g1,'ObjectVisibility','off')

Because object g1 has its ObjectVisibility set to off, it is not visible to commands like instrfind:

instrfind

	Instrument Object Array
	Index:   Type:          Status:     Name:  
	1        serial         closed      Serial-COM1
	2        serial         closed      Serial-COM2

However, instrfindall finds all objects regardless of the value of ObjectVisibility:

instrfindall

	Instrument Object Array
	Index:   Type:          Status:     Name:  
	1        serial         closed      Serial-COM1
	2        serial         closed      Serial-COM2
	3        gpib           closed      GPIB0-2

The following statements use instrfindall to return objects with specific property settings, which are passed as cell arrays:

props = {'PrimaryAddress','SecondaryAddress};
vals = {2,0};
obj = instrfindall(props,vals);

You can use instrfindall as an argument when you want to apply the command to all objects, visible and invisible. For example, the following statement makes all objects visible:

set(instrfindall,'ObjectVisibility','on')

See Also

instrfind | ObjectVisibility | propinfo

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