Page 155 - ExtendSim User Guide
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Items, Properties, and Values 129
Item properties
With the three different types of attributes, the Set dialog could look like:
After attributes have been created, they must be attached to items in the model and they must have unique values assigned to them.
Selecting attributes and attaching them to items
To allow an attribute to be used, define the attribute and assign a value to it. This is done using one of the attribute-handling blocks, such as Set or Create.
The most common method for assigning attributes to an item is to select an attribute in the dia- log of a Set block, then pass the items through the block. The value of the attribute can be defined in the Set’s dialog or through its value input connectors.
Another commonly used block is the Create block when it is in “Create items by schedule” mode. This is a convenient way to initialize new items with a set of attributes as they are intro- duced into the model. In the Create’s schedule table, you can select an attribute from a popup menu in one of the columns, then enter a value for that attribute for each Create Time row in the table. An item generated at the specified times will have the attribute name and value indi- cated in the table. Other blocks, like the Resource Item block, can also be used to attach attri- butes to items.
☞ The information that follows assumes that you are using the Set block to assign an attribute to an item and that you have already created the attribute using a method described on page 128.
Value attribute
To set a value item attribute, select an attribute in the Property Name column’s popup menu. (Existing value attributes are listed below the New Value Attribute divider.) Then enter a number in the Value column. In the screenshot at right, the Size attribute has been selected and 14 has been entered as the value.
String attribute
To set a string item attribute, select an existing attribute
(listed below the New String Attribute divider) from
the popup menu in the Property Name column. Then
click the cell in the Value column to bring up a popup
menu containing all the string values that have been
defined for the attribute. In the example at right, the
selected string attribute is CarType and the Value popup menu contains the strings Ford, Toy-
Discrete Event

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