From: dblack@...
Date: 2007-09-04T05:40:15+09:00
Subject: Re: array of hashes: finding hash with min value for key

Hi --

On Tue, 4 Sep 2007, Patrick Cotner wrote:

> I'm trying to write a proggy to help me figure out how long it will take
> to pay off a credit card based on a payment value.
> The card can have multiple sections with different owed amounts and
> aprs.
> Since the credit card companies pay off lower interest sections prior to
> higher, I need to be able to determine which section has lowest apr. For
> example
>
> <code>
> sections << { :type => "Purchases", :owed => 840.64, :apr => 0.2474 }
> sections << { :type => "Transfers", :owed => 3453.45, :apr => 0.1774 }
>
> </code>
>
> I've set up a loop to iterate through each section and apply a finance
> charge to the owed amounts.  I have a variable with my payment amount.
> After applying the finance charge, i need to see if section[:apr] is the
> lowest of all sections, in order to apply the payment to that section
> only.
> How would this be done?

You could say:

   lower = sections.find {|s| s[:apr] < section[:apr] }

and if that's non-nil, you've found a lower one.


David

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