Array of indexes to array of ranges

Question

Ranges in ruby are pretty cool. I end up with arrays such as this:

geneRanges = [(234..25), (500..510), (1640..1653)]

And subsequently ha

Answer 1

Here's an answer (adapted from this code) that is more than twice as fast as the other code posted here. Further, only this answer and the one by @Steve handle arrays of non-integers.

class Array
  def to_ranges
    return [] if empty?
    [].tap do |ranges|
      init,last = first
      each do |o|
        if last && o != last.succ
          ranges << (init..last)
          init = o
        end
        last = o
      end
      ranges << (init..last)
    end
  end
end

Here are the benchmark results:

                 user     system      total        real
steve        1.107000   0.000000   1.107000 (  1.106221)
wayne        1.092000   0.000000   1.092000 (  1.099220)
user229426   0.531000   0.000000   0.531000 (  0.523104)
mladen1      0.780000   0.000000   0.780000 (  0.774154)
mladen2      0.780000   0.000000   0.780000 (  0.792159)
phrogz       0.218000   0.000000   0.218000 (  0.220044)

All benchmarked code was adapted to remove sort.uniq for a fair comparison.