Class: Capricious::Erlang

Inherits:
Object
  • Object
show all
Includes:
PRNG
Defined in:
lib/capricious/erlang.rb

Overview

Models the Erlang distribution, parameterized on the lambda value of the underlying exponential distribution and a shape parameter.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from PRNG

included, #next, #prng_initialize, #reset

Constructor Details

#initialize(l, shape, seed = nil, policy = MWC5, keep_stats = false) ⇒ Erlang

Initializes a new Erlang distribution. =l= is the lambda parameter and

shape= is the shape parameter; =seed=, =policy=, and =keep_stats= are

as in =PRNG=.



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# File 'lib/capricious/erlang.rb', line 33

def initialize(l, shape, seed=nil, policy=MWC5, keep_stats=false)
  @shape = shape
  @expected_mean = shape / l.to_f
  @expected_variance = shape / (l * l).to_f
  @expo = Exponential.new(l, seed, policy, keep_stats)
  prng_initialize(seed, policy, keep_stats)
end

Instance Attribute Details

#expected_mean ⇒ Object (readonly)

Returns the value of attribute expected_mean.



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# File 'lib/capricious/erlang.rb', line 28

def expected_mean
  @expected_mean
end

#expected_variance ⇒ Object (readonly)

Returns the value of attribute expected_variance.



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# File 'lib/capricious/erlang.rb', line 28

def expected_variance
  @expected_variance
end