From: Joel VanderWerf <vjoel@...>
Date: 2009-04-30T04:23:37+09:00
Subject: Re: Finding Matches in Array of Classes

Rob Redmon wrote:
> I have an ActiveRecord find result.  An element's contents look like:
> 
> irb(main):090:0> results[0]
> => #<InventoryHour id: 47475, observation_time: "2008-01-01 00:00:00",
> station_id: 6, extension_id: 22, disk: 4, archive: 0, updated_on:
> "2009-04-15 15:57:16">
> 
> The class of "observation_time" is:
> results[0].observation_time.class
> => Time
> 
> 
> What I'd like to do is find those elements which match on a particular
> range of "observation_time".  I'm used to Matlab and IDL programming
> where one just does something like this:
> 
> indices = where( results.observation_time >= "2008-1-1" and
> results.observation_time < "2009-1-1" )
> 
> What's the ruby way?  Obviously, I can't use Array.include? but
> something like that would be nice.
> 
> Rob

require 'time'
range = Time.parse("2008-1-1")..Time.parse("2009-1-1")
results.select {|r| range.include? r.observation_time}

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407