Page 380 - ExtendSim User Guide
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354 Creating Flow
Flow attributes
Types of flow attributes
ExtendSim supports two types of flow attributes for Rate library blocks:
• Alayerattributeholdsarealnumberasitsattributevalue.
• The value of a string layer attribute is still a number, but it is represented in the model by a string.
With string attributes you choose a descriptive text label (string) for each potential value of the flow attribute; the information is entered in a lookup table in the Executive block's Flow Attri- butes tab. The string can then be used in the model in place of the corresponding number. For example, a string layer attribute named Flavor might have three possible values: 1, 2, and 3. Once the lookup table for this attribute has been properly configured, the blocks referencing the Flavor attribute will display the strings Vanilla, Berries, or Caramel instead of the numbers 1, 2, and 3. For instance, see the string layer attribute Flavor in the Executive, below.
Creating and assigning a flow attribute
There are several methods for creating a new flow attribute:
• Use the Set(R) block
• UsetheTank,iftheinitialcontentsisset using flow attribute values
• Use the Merge and Diverge, if you cus- tomize how attributes behave at their inflows or outflows
• The Interchange block has a mapping
capability such that item attributes can be mapped to flow attributes, and vice versa.
To create a new flow attribute in the Set(R) block, use the green +/- resize button to add any needed rows to the table in its dialog. Then use the pop-ups at the top of the columns to add a new layer or new string layer attribute, give it a name, and (in the case of a layer attribute) assign an initial attribute value. Selecting a string layer attribute type causes the Executive to open to the Flow Attributes tab shown on page 356; this is where strings that correspond to the
Discrete Rate

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