From: "David A. Black" <dblack@...>
Date: 2009-07-22T07:41:56+09:00
Subject: Re: Standard Deviation question regarding EDOM errors

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Hi --

On Wed, 22 Jul 2009, Älphä Blüë wrote:

>  def product
>    @arr.inject {|a,b| a * b }
>  end

>  product, sum = 0.0, 0.0
>  arr.each do |a|
>    sum += a
>    product += a*a
>  end

The logic in the second snippet is wrong (assuming the logic in the
product method is what you want). Try it with [1,2], for example, and
you'll get 2 for the first one and 5 for the second.


David

-- 
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