Question

I’m trying to determine a rank for each key in a hash against the other keys based on it’s value. The value is numeric. Ranks can be repeated (i.e. 3 keys can tie for first place). This works, but is ugly.

standings.sort_by {|k, v| v}.reverse!
prev_k = nil
standings.each_with_index do |(k, v), i|
  if i == 0
    k.rank = 1
  elsif v == standings[prev_k]
    k.rank = prev_k.rank
  else
    k.rank = prev_k.rank + 1
  end
  prev_k = k
end

Answer 1

Give this a try:

ranks = Hash[standings.values.sort.uniq.reverse.each_with_index.to_a]
standings.each { |k, v| k.rank = ranks[v] + 1 }

I’m not sure it’s any prettier, but it’s a bit more compact, carries fewer loop variables, and has no conditionals.