Variables Guide

1 • VARIABLES
expression when using autostates. For example, STATE(Resource ID) == IDLE_RES
returns true if Resource ID is currently in the idle autostate.
IDLE_RES—Resource state constant. The IDLE_RESource is used in an expression
to check whether a resource is currently in the idle state. A resource is in the idle state
when all units are idle and the resource is not failed or inactive. (The numerical
equivalent of this variable is -1.)
BUSY_RES—Resource state constant. The BUSY_RESource is used in an expression
to check whether a resource is currently in the busy state. A resource is in the busy
state when it has one or more busy units. (The numerical equivalent of this variable is
-2.)
INACTIVE_RES—Resource state constant. The INACTIVE_RESource is used in an
expression to check whether a resource is currently in the inactive state. A resource is
in the inactive state when it has 0 capacity and is not failed. (The numerical equivalent
of this variable is -3.)
FAILED_RES—Resource state constant. The FAILED_RESource is used in an
expression to check whether a resource is currently in the failed state. A resource is in
the failed state when a failure is currently acting on the resource. (The numerical
equivalent of this variable is -4.)
Resource cost variables
One major component of costs in many models is the cost associated with resources.
These costs are in three categories: costs applied during the time a resource is busy,
costs applied during the time a resource is idle (scheduled, but not busy), and costs
applied each time a resource is used (regardless of how long it is used).
If both the costing statistics and the resource statistics options are enabled on the Run
> Setup > Project Parameters property page, resource costs will be calculated and
reported automatically. The following variables are supplied if you instead want to
calculate resource costs manually. Note that you should not do both manual and
automatic calculations concurrently or both may report incorrect results.
ResBusyCost ( Resource ID )—Resource busy cost rate. This returns the busy cost
rate specified in the resource module. This rate is the cost per time unit to be applied
during the entire time a resource is busy. Note that although this rate is entered as a
cost per hour, this variable always returns the rate as a cost per base time unit (for
example, TNOW units). So regardless of the current settings for base time units, this
rate can be used without conversion.
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