getNamespace

OPC HDA server namespace

Syntax

serverNamespace = getNamespace(hdaObj)

serverNamespace = getNamespace(hdaObj,Name=Value)

Description

serverNamespace = getNamespace(hdaObj) retrieves the entire server namespace from the connected OPC HDA Client hdaObj.

serverNamespace = getNamespace(hdaObj,Name=Value) retrieves a part of the server namespace based on the options specified in the name-value arguments.

Examples

Retrieve Entire Namespace

Get the entire namespace for the Matrikon™ Simulation Server on the local host

hdaObj = opchda('localhost','Matrikon.OPC.Simulation');
connect(hdaObj); 
nsFull = getNamespace(hdaObj)

nsFull = 

  5×1 struct array with fields:

    Name
    FullyQualifiedID
    NodeType
    Nodes

Retrieve Specific Part of Namespace

Get only the first level of the namespace.

nsPart = getNamespace(hdaObj,Depth=1);

Add the nodes contained in the first branch of the namespace to the existing structure.

nsPart(1).Nodes = getNamespace(hdaObj, ... 
    StartItemID=nsPart(1).FullyQualifiedID, ... 
    Depth=1);

nsPart = 

  5×1 struct array with fields:

    Name
    FullyQualifiedID
    NodeType
    Nodes

Input Arguments

hdaObj — OPC HDA client

OPC HDA client object

OPC HDA client, specified as an OPC HDA client object.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: nsPart = getNamespace(hdaObj, StartItemID="Simulation Items", Depth=2);

StartItemID — Fully qualified item ID

character vector | string

Fully qualified item ID, specified as a character vector or string. The function retrieves the server namespace beginning at the specified fully qualified item ID, and all branches in the namespace below it.

Example: nsPart = getNamespace(hdaObj, StartItemID="Config Items");

Data Types: char | string

Depth — Number of levels of namespace

positive integer

Number of levels of server namespace to retrieve beginning with the server namespace root, specified as a positive integer. Specifying Depth as 1 retrieves only the nodes (branch and leaf) contained in the root of the server namespace.

Example: nsPart = getNamespace(hdaObj, Depth=1);

Data Types: double

Output Arguments

serverNamespace — Server namespace

array of structures

Server namespace, returned as a recursive array of structures. Each structure in the array represents a node and contains these fields:

• Name— Descriptive name for the node.

• FullyQualifiedID— Fully qualified ItemID of the node.

• NodeType— Type of node returned as 'branch' node (when the node contains other nodes) or 'leaf' node (when the node does not contain other nodes)

• Nodes— Array of structures representing the nodes contained in this branch of the namespace. The structures in this array have the same fields as the serverNamespace.

Version History

Introduced in R2011a