Re: Imprecision of DAYS_PER_MONTH

Bruno Wolff III wrote:
> On Thu, Jul 21, 2005 at 09:39:38 -0400,
> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> wrote:
> >
> > I have added this comment above the DAYS_PER_MONTH macro:
> >
> > + /*
> > + * DAYS_PER_MONTH is very imprecise. The more accurate value is
> > + * 365.25/12 = 30.4375, or '30 days 10:30:00'. Right now we only
> > + * return an integral number of days, but someday perhaps we should
> > + * also return a 'time' value to be used as well.
> > + */
> > #define DAYS_PER_MONTH 30 /* assumes exactly 30 days per month */
> >
> > Let me add that we could actually do this in many places now because we
> > are already converting to 'time' in those places. Is this a TODO?
>
> Shouldn't you be using 365.2425/12 (30.436875) for the number of days per
> month?

OK, comment updated:

/*
* DAYS_PER_MONTH is very imprecise. The more accurate value is
* 365.2425/12 = 30.436875, or '30 days 10:29:06'. Right now we only
* return an integral number of days, but someday perhaps we should
* also return a 'time' value to be used as well.
*/

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