Expressing time.

Re: Expressing time.

"Sean" <[email protected]> writes:
[color=blue]
>I'm playing around times and dates. I'd like to determine the age of
>particular sets of data in a user friendly matter.[/color]
[color=blue]
>I've got everything ready but dealing with time in a user friendly manner.[/color]
[color=blue]
>What would be a good way to express (in python):
> time.localtime( )+30 days
> time.localtime( )+5 minutes
> time.localtime( )+2 months
> time.localtime( )-2 years[/color]
[color=blue]
>Is there any python facilities to make this an easier chore (aka
>time.localtime ()+months(3))?
>(I included months as it is a special case in that you can't just
>arbitrarily calculate months in seconds without being relative to a
>particular month).[/color]

mx.DateTime makes these sort of calculations easy. I have a similarish task
in presenting users an easy way of specifying which day's log files to search
(hence in this case it was always a date in the past but the principle would
be similar). So I allow things like 'monday', 'tuesday' etc. and -n for n
days ago and several other variations. The interesting one in this instance
is:

dm_reg = re.compile (r'^(-?\d\d?)[/.](-?\d\d?)$')
this_day = today()

# dd/mm (-ve dd means count from end of month, -mm is mm months ago)
mt = re.match (dm_reg, user_input)
if mt:
dy,mon = map(int, mt.groups())
if mon < 0:
mon = this_day.month + mon
if mon <= 0:
mon = 12 + mon
dt = DateTime (this_day.year, mon, dy)
if dt > this_day:
dt = DateTime (this_day.year-1, mon, dy)
return dt

Which allows eg 1/-2 for the first of whatever month was 2 months ago or even
-1/-1 for the last day of the previous month. mx.DateTime is doing all the
hard work. You could cook up something similar to parse eg "-2m" "+2y" etc.

Possibly the new time stuff in 2.3 will do this also, I haven't looked at 2.3
yet.

Eddie