Modifying Action Diagrams › Understanding Built-In Functions › Selection Parameters for Date Built-In Functions › Duration

Duration

The *DURATION built-in function calculates the elapsed time between a beginning date and an ending date.

Note: You should check the return code set by this function in order to catch any errors encountered. This function is the converse of the *DATE INCREMENT built-in function.

The *DURATION built-in function performs the operation:

*Duration = *Date1 - *Date2

The result is positive if *Date1 is after *Date2; it is negative if *Date1 is before *Date2.

There are eight parameters for this function type:

• Seven input parameters
  • *Date2 and *Date1 specify the beginning and ending dates, respectively. When either date is of type NBR, it is interpreted as the number of days since January 1, 1801 (day one).
  • *Duration type specifies the meaning of the result of the operation. See the table at the end of this topic.
  • *Excluded days of week specifies the days to exclude from the operation; for example, weekends or days not worked by part-time employees.
  • *Date List name specifies the name of an existing date list. Date lists let you override normal selection rules set by the *Excluded days of week parameter for particular dates. The specified date list needs to be in the *Date Lists array when the built-in function executes.
  • *Date list autoload determines whether the function automatically loads the specified date list into the *Date Lists array when the function is executed.
  • *Select days/dates lets you reverse the selection determined by the *Excluded days of week and *Date List name parameters. The default is to select included dates.
• One output parameter, *Duration. The meaning of this parameter is determined by the value of *Duration type.

Note: The *Date list, *Excluded days of week, and *Select days/dates parameters affect only days/dates after the beginning date. If the ending date is before the beginning date, these parameters affect only days/dates after the ending date.

For more information on the selection input parameters, see the Selection Parameters for Date Built-In Functions topic in the *DATE DETAILS built-in function description.

The possible values for *Duration type and the effect each has on the meaning of *Duration are shown in the following table.