ruby: sum corresponding members of two or more arrays

Question

I\'ve got two (or more) arrays with 12 integers in each (corresponding to values for each month). All I want is to add them together so that I\'ve got a single array with su

Answer 1

For:

a = [1,2,3]
b = [4,5,6]

You could zip and then use reduce:

p a.zip(b).map{|v| v.reduce(:+) }
#=> [5, 7, 9]

Or, if you're sure that array a and b will always be of equal length:

p a.map.with_index { |v, i| v + b[i] }
#=> [5, 7, 9]