Benchmark binary search vs. iterative search

result

                        user     system      total        real
Binary - Bill:       0.000000   0.000000   0.000000 (  0.000014)
Iterative - Bill:    0.000000   0.000000   0.000000 (  0.000012)
Binary - Bob:        0.000000   0.000000   0.000000 (  0.000020)
Iterative - Bob:     0.000000   0.000000   0.000000 (  0.000007)
Binary - Joe:        0.000000   0.000000   0.000000 (  0.000005)
Iterative - Joe:     0.000000   0.000000   0.000000 (  0.000005)
Binary - Sally:      0.000000   0.000000   0.000000 (  0.000007)
Iterative - Sally:   0.000000   0.000000   0.000000 (  0.000005)
Binary - Sussie:     0.000000   0.000000   0.000000 (  0.000007)
Iterative - Sussie:  0.000000   0.000000   0.000000 (  0.000005)
Binary - None:       0.000000   0.000000   0.000000 (  0.000006)
Iterative - None:    0.000000   0.000000   0.000000 (  0.000005)

test.rb

def binary_search(name, array)
  lower = 0
  upper = array.length - 1

  while lower <= upper
    mid = (lower + upper) / 2
    mid_name = array[mid]

    if name == mid_name
      return array[mid]
    elsif name < mid_name
      upper = mid - 1
    elsif name> mid_name
      lower = mid + 1
    end
  end

  return nil
end

def iterative_search(name, array)
  i = 0

  while i <= (array.length - 1)
    if array[i] == name
      return array[i]
    else
      i += 1
    end
  end

  return nil

end

array_to_search = %w[Bill Bob Joe Sally Sussie]

Benchmark.bm do |x|
  x.report("Binary - Bill: ") {binary_search("Bill", array_to_search)}
  x.report("Iterative - Bill: ") {iterative_search("Bill", array_to_search)}
  x.report("Binary - Bob: ") {binary_search("Bob", array_to_search)}
  x.report("Iterative - Bob: ") {iterative_search("Bob", array_to_search)}
  x.report("Binary - Joe: ") {binary_search("Joe", array_to_search)}
  x.report("Iterative - Joe: ") {iterative_search("Joe", array_to_search)}
  x.report("Binary - Sally: ") {binary_search("Sally", array_to_search)}
  x.report("Iterative - Sally: ") {iterative_search("Sally", array_to_search)}
  x.report("Binary - Sussie: ") {binary_search("Sussie", array_to_search)}
  x.report("Iterative - Sussie: ") {iterative_search("Sussie", array_to_search)}
  x.report("Binary - None: ") {binary_search("None", array_to_search)}
  x.report("Iterative - None: ") {iterative_search("None", array_to_search)}
end