[R] Truncating dates (and other date-time manipulations)

[hadley wickham]

Dear all,

I've been struggling to perform common operations on dates that I need
to be able to correct draw date-time scales - in particular I need to
be able to round/truncate/ceiling dates to arbitrary precision - e.g.
to weeks, months or years (or multiples thereof).  I haven't been able
to find anything to do this in base R (trunc.Date only truncates to
sub-day units), or in the date related contributed packages I've
looked in (e.g. chron).  Have I missed something?

Otherwise, I have been working on a bottom up set of functions to make
date manipulation easier - http://gist.github.com/10238.  These should
work for all date-time types and I've tried to use a consistent naming
scheme and consistent output conventions.  This seems like a rather
small bundle of functions to be worth turning into a package, so I was
wondering if anyone would be interested in adopting them into an
existing date-time related package.

Regards,

Hadley

-- 
http://had.co.nz/