I think it's part misunderstanding and part bad documentation. Looking at DateTime, the subtract_datetime method returns a DateTime::Duration object. Looking at DateTime::Duration hours method, it's a a wrapper over the in_units method which when asking for hours, does an int on the numbers, effectively rounding the value (but probably not in a way you want).

-derby

update: I prefer Date::Manip for date calculations.

In reply to Re: DateTime usage for duration computation by derby
in thread DateTime usage for duration computation by Marsel

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