From: Gary Wright <gwtmp01@...>
Date: 2010-02-10T03:53:35+09:00
Subject: Re: [Q] algorithm to truncate date to beginning of week?


On Feb 9, 2010, at 1:32 PM, Chuck Remes wrote:

> I need to be able to take any date after Jan 1, 1980 and truncate it to the nearest week.
> 
> Example:
> 
> Wed Jan 09 17:53:23 -0600 1980 should truncate to Sun Jan 06 00:00:00 -0600 1980
> 
> Tue Feb 09 12:29:51 -0600 2010 should truncate to Sun Feb 07 00:00:00 -0600 2010
> 
> I've tried all sorts of tricks with modulus (% operator) on the integer representation of time but I can't get anything to work over a range of dates. 
> 
> Anyone have any bright ideas?

>> require 'active_support'
=> true
>> Time.now.beginning_of_week
=> Mon Feb 08 00:00:00 -0500 2010
>> 

It also looks like midnight is considered part of the next day not the previous day as in your example.

Gary Wright