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 FileMaker Pro Custom Functions

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  Average rating: 4.6  (28 votes)
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Darrin Morton, Neocode Software

finds date of Monday in week of any given date

Sample Input:
Sample Output:

 Then copy & paste into FileMaker Advanced's Edit Custom Function window.


Finds the date of the Monday in the week of any given date. Always assumes by convention that Sunday is the first day of the week. (day 1)

input - ( DayOfWeek ( input ) ) + 2

Note: these functions are not guaranteed or supported by Please contact the individual developer with any questions or problems.

This is my Custom Function and I want to edit it


What about:

input - DayOfWeek ( input ) + 2

Daniele Raybaudi, Rome
August 02, 2013 2:01pm

thank you daniele, you were right, your suggestion needed a minor tweak that incorporated, works great

Darrin Morton, Victoria, BC
August 02, 2013 2:31pm

It works even without the added parentheses

Daniele Raybaudi, Rome
August 03, 2013 2:31am

This doesn't give a correct result if the day of the week input is a Sunday. It returns the Monday after, not the Monday before.

If you alter the function to this:
input - DayOfWeek ( input -1 ) + 1
then it gives the previous Monday when a Sunday is specified.

It may be that some people want to calculate it as Darrin specifies, but I was caught out by the Sunday date so thought it best recorded here. Thanks for a useful function though


Brian Rich, Hampshire, UK
June 23, 2014 8:35am

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