Help with multidimensional arrays in Ruby

Question

I have this code to split a string into groups of 3 bytes:

str="hello"
ix=0, iy=0
bytes=[]
tby=[]
str.each_byte do |c|
    if iy==3 
     iy=0
     bytes[ix]=[]
     tby.each_index do |i|
      bytes[ix][i]=tby[i]
     end
     ix+=1
    end
    tby[iy]=c
    iy+=1
end
puts bytes

I've based it on this example: http://www.ruby-forum.com/topic/75570

However I'm getting type errors from it. Thanks.

Answer 1

Your problem is the line

ix=0, iy=0

It sets the value of ix to an array of twice 0, and iy to 0. You should replace it by

ix, iy = 0, 0

Answer 2

ix = 0, iy = 0 translates to ix = [0, (iy = 0)], which is why you get a type error.

However there is a less "procedural" way to do what you want to do:

For ruby 1.8.7+:

"hello world".each_byte.each_slice(3).to_a
#=> [[104, 101, 108], [108, 111, 32], [119, 111, 114], [108, 100]]

For ruby 1.8.6:

require 'enumerator'
"hello world".enum_for(:each_byte).enum_for(:each_slice, 3).to_a