Contents

class Array
  def mean
    self.inject(:+).to_f / self.length
  end

  def arithmetric_mean
    self.mean
  end

  def geometric_mean
    self.inject(:*).to_f ** (1.0 / self.length)
  end

  def harmonic_mean
    self.length / self.map{ |x| 1.0 / x }.inject{ |sum, x| sum + x }.to_f
  end

  def quadratic_mean
    self.power_mean(2)
  end

  def power_mean(p = 1)
    ((1.0 / self.length) * self.map{ |x| x ** p }.inject{ |sum, x| sum + x }.to_f) ** (1.0 / p)
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
rstat-0.0.2	lib/rstat/core_ext/array/mean.rb
rstat-0.0.1	lib/rstat/core_ext/array/mean.rb