From: "David A. Black" <dblack@...>
Date: 2009-07-22T08:03:34+09:00
Subject: Re: Standard Deviation question regarding EDOM errors

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Hi --

On Wed, 22 Jul 2009, Älphä Blüë wrote:

> Hi David,
>
> I think I understand what you are saying..
>
> What I want with..
>
> product += a*a
>
>
> is .. a[0]*a[0]+a[1]*a[1]+a[2]*a[2]..etc.

OK, then the product method in the class is wrong. "Product" doesn't
sound like the right name for a sum-of-the-squares calculation. But
anyway --

   def whatever_you_call_it  # :-)
     @arr.inject(0) {|acc,x| acc + x * x }
   end


David

-- 
David A. Black / Ruby Power and Light, LLC
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