On Tue, Jun 7, 2011 at 9:54 AM, Robert Kern <[email protected]> wrote:
> On Tue, Jun 7, 2011 at 07:34, Dave Hirschfeld <[email protected]> > wrote: > > > I'm not convinced about the events concept - it seems to add complexity > > for something which could be accomplished better in other ways. A [Y]//4 > > dtype is better specified as [3M] dtype, a [D]//100 is an [864S]. There > > may well be a good reason for it however I can't see the need for it in > my > > own applications. > > Well, [D/100] doesn't represent [864s]. It represents something that > happens 100 times a day, but not necessarily at precise regular > intervals. For example, suppose that I am representing payments that > happen twice a month, say on the 1st and 15th of every month, or the > 5th and 20th. I would use [M/2] to represent that. It's not [2W], and > it's not [15D]. It's twice a month. > > The default conversions may seem to imply that [D/100] is equivalent > to [864s], but they are not intended to. They are just a starting > point for one to write one's own, more specific conversions. > Similarly, we have default conversions from low frequencies to high > frequencies defaulting to representing the higher precision event at > the beginning of the low frequency interval. E.g. for days->seconds, > we assume that the day is representing the initial second at midnight > of that day. We then use offsets to allow the user to add more > information to specify it more precisely. > > Ah, it's a new concept: DeltaTime as a container of events ;) And what did you do during Summer vacation? Chuck
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