Rounding a timestamp?!
Can you round a timestamp up or down by an incriment? Such as 0:30:00 or 0:15:00?
You appear to want to round to the nearest quarter hour. TimeStamps record elapsed time in seconds just as Time fields do so
Adapting from a very old Knowledgebase article, (http://help.filemaker.com/app/answers/detail/a_id/4587/kw/round/related/1) this expression should do that for you:
Round (TimeStampField/900, 0) * 900
Be sure to select TimeStamp as your return type.
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