Method: Statistics::Distribution::ChiSquared#density_function

Defined in:
lib/statistics/distribution/chi_squared.rb

#density_function(value) ⇒ Object 



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# File 'lib/statistics/distribution/chi_squared.rb', line 17

def density_function(value)
  return 0 if value < 0

  common = degrees_of_freedom/2.0

  left_down = (2 ** common) * Math.gamma(common)
  right = (value ** (common - 1)) * Math.exp(-(value/2.0))

  (1.0/left_down) * right
end