5g: IsOccurrenceDateλ()
Description
IsOccurenceDateλ() is used to determine if a date is when items that may, or may not repeat on regular intervals, happen. This is useful for project planning where there are many tasks, resources, and expenses need to be scheduled. It is also useful for zero based, rotating budgeting where recurring expenses are common.
Syntax
IsOccurenceDateλ( Dates, FirstOccurence, [LastOccurence], [Repeats], [Diagnostics])
Dates
(Required) Date to test. Normally this is horizontal timeline by day
FirstOccurence
(Required) When something that may repeat, happens for the first time.
LastOccurence
(Optional) When something that may repeat, happens for the last time. If omitted, it will be assumed the item repeats indefinitely.
Repeats
(Optional) A code that conveys how often this item repeats. If omitted, it wil be assumed the item does not repeat. Repeat codes are
O=One time/never repeats (default)
A=Annually
S=Semi-Annually
Q=Quarterly
M=Monthly
B=BiWeekly
W=Weekly
X=Every Workday (USA normal)
D=Daily
Diagnostics
(Optional) If TRUE, input errors that can occur after formula entry will display as diagnostic messages. The default is FALSE. It is recommended that models have a named range called Diagnostics and this named range be set to TRUE during model development and then set to FALSE when the model is placed into production.
Example
In this example we are scheduling several items that start on various dates. Some repeat at regular intervals and some never repeat. Of those that repeat, some repeat forever and some end on a specific date.
The result of IsOccurenceDateλ is an array of TRUE and FALSE which we can convert to flags (1, 0) by applying the N() function to this component.
The timeline must be in days.