Elapsed Time Calculation
Filemaker Pro Advanced 10.0v1Windows Vista The problem occures when calculating elapsed time at the end/beginning of the day, eg., if start time = 11PM and end time = 12AM (midnight) end time - start time SHOULD = 1 hour, instead the result returned is -23:00:00. On the other hand, if for a start time you use 12AM or 0AM for start time and 9AM for end time, the result of end time - start time returns 9 hour. In fact 9AM -12AM SHOULD return the -23:00:00. I understand the mathmatical quandry here but I think from a user interface prespective it makes more sense to make 12PM be the very last miniscule second of the day and 0 to be the starting instant of the new day. That way you can have 24 hours in a day by subtracting start time (0) from end time (12PM). Not Possible at the moment. Best regards, Bruce PS. I hate reporting "annomallys" w/o also saying how great this program is. I absolutely love it and I can easilly work around this problem BUT I'm trying to make an application where my users probably won't understand the "work around".
Filemaker counts time as the number of seconds elapsed since midnight. And midnight is midnight, whether you choose to display it as 0:00:00 or 12:00:00 AM.
If you want time differences to be always positive (i.e. assume that a negative result is due to crossing midnight), use a calculation =
Mod ( EndTime - StartTime ; 86400 )
or change your fields type to Timestamp.