From: "Wesley J. Landaker" <wjl@...>
Date: 2003-08-29T22:55:25+09:00
Subject: Re: multiply all array with array

Apparently, ibotty recently wrote:
> before i spent to many words describing something so simple:
>
> say, i have:
> a = [1,2,3] and b = [4,5,6]
> and i want to get another array, with c[ix] = a[ix] * b[ix].
> (i want to get c = [4,10,18])
>
> is there a builtin function in array.rb (that i have missed).
>
> atm, i use a block to traverse thru every single element, but this still
> makes one big or 2 small lines.
> (e. g.: c =[]; a.each_with_index{ |ix| c[ix] = a[ix] * b[ix] } )
>
> this should be way more elegant ;)

I don't know if this is more elegant to you or not, but here is another way:

c = a.zip(b).map {|x| x[0] * x[1]}

Wes