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Resources and Shifts 265
Resource requirements
• FC#2–filterusingaresourcepropertyTotalIdleTimethathasthecondition>10
• FC#3 – filter using a group property Skill Level that has the condition = 2
• FC#4 – filter using a resource property Group that has the condition = Group A
As discussed below, saved filtering conditions are used to create a quantity expression.
Quantity expressions
Defining quantity expressions is the second step towards creating a resource requirement. A quantity expression is a logical statement that is used to select a certain quantity of resources from an identified collection of resources. The collection of resources is limited by the combi- nation of filtering conditions that is entered in the expression, which can be quite complicated. However, for each quantity expression only the specified quantity of qualifying resources will be drawn from the entire identified collection.
Each quantity expression consists of three clauses:
1) AQuantityclausethatspecifieshowmanyresourcestoselectfromaresourcecollection.
2) AWHEREclausethatgeneratestheresourcecollection.TheWHEREclausecontainsthe criteria that resources must satisfy in order to be selected. The criteria are specified using one or more filtering conditions.
3) AnoptionalOrderByclausethatisusedtosortthecollectionofresourcesgeneratedbythe WHERE clause. The collection of resources is sorted based on the values (in ascending or descending order) of a selected resource property.
When the simulation is run, the quantity expression will be applied as shown below:
How a quantity expression gets applied during the simulation run (“Order By” is optional)
The Create/modify quantity expres-
sions frame (Resource Manager’s
Requirements tab) is for specifying
the quantity of resources to be drawn
from a set of resources defined by filtering conditions. The result is then saved as a quantity expression for use when building a resource requirement.
Discrete Event

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