From: Jeremy Hinegardner <jeremy@...>
Date: 2007-09-27T13:16:51+09:00
Subject: Re: Finding the last Sunday of a month

On Wed, Sep 26, 2007 at 10:44:42PM +0900, Peter Bailey wrote:
> Hello,
> I need to find the date for the last Sunday in January, for any year. I
> need this for a budgetary script I'm trying to write. Using the
> Date/Time module, I've done this so far.
> 
> require 'date'
> now = DateTime.now
> year = now.year
> d = Date.new(now.year, 1, 31)
> puts d.wday
> 
> yields: 3
> 
> This tells me that the last day of January is a Wednesday. But, I need
> that last Sunday. Is there a method in 'date' that can give me the date
> of the last Sunday? The last Sundays of each month are the boundaries
> for my company's budget periods.

Well this has been answered fully now, but just for fun, how about the
fully gem driven method:

    % cat last_sun_jan.rb 
    require 'rubygems'
    require 'chronic'
    require 'facet/times'
    require 'facet/time/to_date'

    last_sunday_in_jan = (Chronic.parse("1st Sunday in February", :context => :future) - 7.days).to_date

    puts last_sunday_in_jan

    % ruby last_sun_jan.rb
    2008-01-27

enjoy,

-jeremy

-- 
========================================================================
 Jeremy Hinegardner                              jeremy@hinegardner.org