From: Todd Benson <caduceass@...>
Date: 2008-05-15T07:14:40+09:00
Subject: Re: changing hash key

On Wed, May 14, 2008 at 1:35 PM, Adam Shelly <adam.shelly@gmail.com> wrote:

> account_map = {
>   "sticky" => (500..539),
>   "stinky" => (540..550)
> }
> # fill @account_balances...
>
> account_summary= Hash.new
> account_map.each{|name,range|
>    account_summary[name]= @account_balances.select{|act_num, balance|
>        range.include? (act_num)
>    }
>  }
> account_summary.each{|name, subtotals|
>  total = subtotals.map{|act_num,balance|balance}.sum

Just FYI to ruby nubies:  The #sum method for addition in enumerables
is available in libraries (included with Rails, for example), but not
in ruby 1.8.6 itself.  I don't know the status of ruby 1.9 on that
one.

Todd