Class: Statistical::Rng::Exponential

Inherits:
Object
  • Object
show all
Defined in:
lib/statistical/rng/exponential.rb

Overview

Companion RNG class for the exponential distribution. Requires a

distrbution object of the corresponding distribution

Author:

  • Vaibhav Yenamandra

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(dobj = nil, seed = Random.new_seed) ⇒ Exponential

Returns a new instance of Exponential.



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# File 'lib/statistical/rng/exponential.rb', line 17

def initialize(dobj = nil, seed = Random.new_seed)
  unless dobj.nil? || dobj.is_a?(Statistical::Distribution::Exponential)
    raise TypeError,
          "Expected Distribution object or nil, found #{dobj.class}"
  end
  dobj = Statistical::Distribution::Exponential.new if dobj.nil?
  @generator = Random.new(seed)
  @rate = dobj.rate
  @sdist = dobj
end

Instance Attribute Details

#generator ⇒ Object (readonly)

Returns the value of attribute generator.



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# File 'lib/statistical/rng/exponential.rb', line 15

def generator
  @generator
end

#rate ⇒ Numeric (readonly)

Rate parameter of the exponential distribution

Returns:

  • (Numeric) —

    the current value of rate



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# File 'lib/statistical/rng/exponential.rb', line 14

def rate
  @rate
end

#upper ⇒ Numeric (readonly)

The upper bound of the uniform distribution

Returns:

  • (Numeric) —

    the current value of upper



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# File 'lib/statistical/rng/exponential.rb', line 14

def upper
  @upper
end

Instance Method Details

#rand ⇒ Numeric

Return the next random number from the sequence

Returns:

  • (Numeric) —

    next random number in the sequence



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# File 'lib/statistical/rng/exponential.rb', line 31

def rand
  return @sdist.quantile(@generator.rand)
end

#type ⇒ Object

Return the type of the source distribution

Returns:

  • source distribution’s type



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# File 'lib/statistical/rng/exponential.rb', line 48

def type
  @sdist.class
end