The reactor aims to clean up some of the maps but ultimately to allow users
to specify strings there has to be some mapping from string to offsets.

That being said there could be something done to defer the creation of the
objects.
On Oct 11, 2013 8:58 PM, "Jeff Tratner" <notifications@github.com> wrote:

> In pandas/tseries/frequencies.py:
>
> > +    for _weekday in range(7):
> > +        for _imonth in range(1,12+1):
> > +
> > +            for variation in ["nearest", "last"]:
> > +                offset = offsets.FY5253(startingMonth=_imonth,
> > +                                        weekday=_weekday,
> > +                                        variation=variation)
> > +                add_offset_to_map(offset)
> > +
> > +            for qtr_with_extra_week in range(1,4+1):
> > +                for variation in ["nearest", "last"]:
> > +                    offset = offsets.FY5253Quarter(startingMonth=_imonth,
> > +                                 weekday=_weekday,
> > +                                 qtr_with_extra_week=qtr_with_extra_week,
> > +                                 variation=variation)
> > +                    add_offset_to_map(offset)
>
> Feels like a lot and it seems like there should be a better way. Doesn't
> impact lookup times, certainly adds to pandas already-long load times
> (though it doesn't add that much). I guess I just wonder about what we do
> when someone wants to add another offset that has that many permutations.
> Rather do something better now - maybe you could do that offset refactor
> first and then circle back to this?
>
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>