Turn a number into a letter. Useful for formatting the numbering for alpha lists. Uses Words notation so when it reaches z it will continue aa, bb, cc, etc.

number_to_letter.rb

def number_to_letter(n=1)
  nums = *'a'..'z'
  nums[(n % 26) - 1] * ((n-1) / 26 + 1)
end

# Smart ass one line edition by @krolaw
# Doesn't use an array
def number_to_letter_revised(n=1)
  ('a'.ord+((n-1) % 26)).chr * ((n-1) / 26 + 1)
end


# Output the result for numbers 1 to 100
(1..100).each{|i| puts "#{i} -> #{number_to_letter(i)}"}