Excerpts from Paul Sholtz's message of Mon Feb 28 12:31:12 -0800 2011:
> That is, I'm stepping through one array, and then I'm "counting" to keep
> track of where I am in the other array, so as to "add" the two arrays.
> 
> I know (before calling the routine) that both arrays are of the same
> size, and that elements of the corresponding arrays will be added
> together.

Sounds like you want zip.

  %w( a b c ).zip( 1..3 ).each {|l, d| puts "# l:#{l}, d:#{d}" }
  # l:a, d:1
  # l:b, d:2
  # l:c, d:3
  # => [["a", 1], ["b", 2], ["c", 3]] 

-- 
med vänlig hälsning
David J. Hamilton