From: rashworth <rashworth@...>
Date: 2001-03-13T06:10:35+09:00
Subject: [ruby-talk:12529] Re: Sum of Squares

Thank you for your note. The new coding worked just fine.
Do you have some code for the Sum of the Cross-Products?
Sumxy = (x1 * y1) + (x2 * y2) + ....

Bob Ashworth

---------- Original Message ----------------------------------
From: Mathieu Bouchard <matju@sympatico.ca>
Reply-To: ruby-talk@ruby-lang.org
Date: Mon, 12 Mar 2001 07:48:05 +0900

>On Mon, 12 Mar 2001, rashworth wrote:
>> # The following code does not Sum the squares of the elements.
>> # Define class Array for Sum of squares
>> class Array
>>   def inject(n)
>>     each { |value| n = yield(n, value) }
>>     n
>
>"nested method definition". you forgot an "end" here.
>
>>   def sumsq
>>     inject(0) { | n, value | (n * n) + value }
>
>this should be
>      inject(0) { | n, value | n + value*value }
>
>matju
>
>