module Enumerable

TODO: Avoid monkey-patching.

Public Instance Methods

mean() click to toggle source
# File lib/enumerable.rb, line 3
def mean
  self.reduce(:+) / self.length.to_f
end
standard_deviation() click to toggle source
# File lib/enumerable.rb, line 12
def standard_deviation
  Math.sqrt(self.variance)
end
variance() click to toggle source
# File lib/enumerable.rb, line 7
def variance
  mean = self.mean
  self.reduce(0) { |memo, value| memo + ((value - mean) ** 2) } / (self.length - 1).to_f
end