scheduled transactions

[Dave Peticolas]

Clark Jones writes:
> Joshua Sled wrote:
> [...]
> >  * For each element of the frequency enum, we must have some set of
> >  * anchors from which to compute the new date.
> >  *
> >  * daily       : N/A
> >  * weekly      : { 0==sun, .., 6==sat }
> >  * biweekly    : start day of month
> >  * semi_monthly: first, second days of month
> >  * bi-monthly  : day of month
> >  * monthly     : day of month
> >  * quarterly   : start month,day in year \
> >  * semi_yearly : first month,day in year  } [watch out for leap day]
> >  * yearly      : day of year             /
> >  **/
> 
> I think you're getting there.  However, I really think that some way should b
> provided for the [ab]user to specify his/her own frequency -- one I can think
> of right off hand that someone might want would be "every 90 days" -- again,
> this differs from "quarterly" as it will "drift" 5 or 6 days a year, and can
> even have five "event days" in one year -- the problem is that this will take
> an "anchor" (day, month, year) and a period.  And as I think of it, I can
> easily come up with one that can only be described as a "series of one-time
> events" -- they _can_ be predicted well in advance (often two or three years)
> but vary slightly from year to year as to the exact "when" -- an example of
> that would be "start of semester".
> 
> A point also just dawned on me:  "biweekly" needs a "day, month, year" anchor
> point -- if it starts on 2-Mar-2001, the next will be 16-Mar-2001, the next
> will be 30-Mar-2001, the next will be 13-Apr-2001 (not 2-Apr-2001!).
> 
> I was about to say that "since we're not trying to write a calendar, I don't
> think we need to deal with think we have to deal with things like 'first
> Thursday in the month' or 'third Wednesday'", but now that I think of it, I
> happen to have an expense that's liked to "first Thursdays" (though at the
> moment it doesn't find its way into Gnucash) -- I always purchase dinner at a
> certain restaurant where a meeting is held that evening.  (I used to also hav
> one that was "Wednesday before first Thursday", which would sometimes fall on
> the last day of the previous month -- but that sort of strangeness is rare
> enough that I'd be willing to have to enter a series of "one-time" events.)
> 
> One bit of simplification, though:  "daily", "weekly", and "biweekly" can all
> just be special cases of "defined period", with a "period" of 1, 7, and 14,
> respectively.

I agree, user-defined periods would be very nice.


> And there's one other related tidbit here:  should we have an ending date?
> I know, for instance, that I have one monthly bill that is due the 12th of
> each month that will have its last payment in May, 2004.  (An alternative
> might be to have the ability to say how many times it will occur.  When one
> signs up for a loan, typically, there will be N payments.)

I think it should be possible to either choose an ending date or to
just leave it as 'eternal until I turn it off'. Some recurring payments
(like loans) have a known ending date. Others, like rent, will end sometime
but the user probably doesn't know exactly when.

dave