Class: Statistics::Distribution::StandardNormal

Inherits:
Normal
  • Object
show all
Defined in:
lib/statistics/distribution/normal.rb

Direct Known Subclasses

InverseStandardNormal

Instance Attribute Summary

Attributes inherited from Normal

#mean, #standard_deviation, #variance

Instance Method Summary collapse

Methods inherited from Normal

#cumulative_function, #random

Constructor Details

#initialize ⇒ StandardNormal

Returns a new instance of StandardNormal.



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# File 'lib/statistics/distribution/normal.rb', line 71

def initialize
  super(0, 1) # Mean = 0, Std = 1
end

Instance Method Details

#density_function(value) ⇒ Object 



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# File 'lib/statistics/distribution/normal.rb', line 75

def density_function(value)
  pow = (value**2)/2.0
  euler = Math.exp(-pow)

  euler/Math.sqrt(2 * Math::PI)
end