Class: RubyStatistics::Distribution::Uniform

Inherits:
Object
  • Object
show all
Defined in:
lib/ruby-statistics/distribution/uniform.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(a, b) ⇒ Uniform

Returns a new instance of Uniform.



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# File 'lib/ruby-statistics/distribution/uniform.rb', line 6

def initialize(a, b)
  self.left = a.to_r
  self.right = b.to_r
end

Instance Attribute Details

#left ⇒ Object

Returns the value of attribute left.



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# File 'lib/ruby-statistics/distribution/uniform.rb', line 4

def left
  @left
end

#right ⇒ Object

Returns the value of attribute right.



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# File 'lib/ruby-statistics/distribution/uniform.rb', line 4

def right
  @right
end

Instance Method Details

#cumulative_function(value) ⇒ Object 



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# File 'lib/ruby-statistics/distribution/uniform.rb', line 19

def cumulative_function(value)
  if value < left
    0
  elsif value >= left && value <= right
    (value - left)/(right - left)
  else
    1
  end
end

#density_function(value) ⇒ Object 



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# File 'lib/ruby-statistics/distribution/uniform.rb', line 11

def density_function(value)
  if value >= left && value <= right
    1/(right - left)
  else
    0
  end
end

#mean ⇒ Object Also known as: median 



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# File 'lib/ruby-statistics/distribution/uniform.rb', line 29

def mean
  (1/2.0) * ( left + right )
end

#variance ⇒ Object 



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# File 'lib/ruby-statistics/distribution/uniform.rb', line 35

def variance
  (1/12.0) * ( right - left ) ** 2
end