Class: Lernen::Algorithm::KearnsVaziraniVPA::KearnsVaziraniVPALearner

Inherits:
Learner
  • Object
show all
Defined in:
lib/lernen/algorithm/kearns_vazirani_vpa/kearns_vazirani_vpa_learner.rb

Overview

KearnzVaziraniVPALearner is an implementation of Kearnz-Vazirani algorithm for VPA.

The idea behind this implementation is described by [Isberner (2015) “Foundations of Active Automata Learning: An Algorithmic Overview”](eldorado.tu-dortmund.de/handle/2003/34282).

Instance Method Summary collapse

Methods inherited from Learner

#add_alphabet, #learn

Constructor Details

#initialize(alphabet, call_alphabet, return_alphabet, sul, cex_processing: :binary) ⇒ KearnsVaziraniVPALearner

: (

  Array[In] alphabet, Array[Call] call_alphabet, Array[Return] return_alphabet,
  System::MooreLikeSUL[In | Call | Return, bool] sul,
  ?cex_processing: cex_processing_method
) -> void



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# File 'lib/lernen/algorithm/kearns_vazirani_vpa/kearns_vazirani_vpa_learner.rb', line 29

def initialize(alphabet, call_alphabet, return_alphabet, sul, cex_processing: :binary)
  super()

  @alphabet = alphabet.dup
  @call_alphabet = call_alphabet.dup
  @return_alphabet = return_alphabet.dup
  @sul = sul
  @cex_processing = cex_processing

  @tree = nil
end

Instance Method Details

#build_hypothesis ⇒ Object 



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# File 'lib/lernen/algorithm/kearns_vazirani_vpa/kearns_vazirani_vpa_learner.rb', line 42

def build_hypothesis
  tree = @tree
  return tree.build_hypothesis if tree

  [build_first_hypothesis, { 0 => [] }]
end

#refine_hypothesis(cex, hypothesis, state_to_prefix) ⇒ Object 



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# File 'lib/lernen/algorithm/kearns_vazirani_vpa/kearns_vazirani_vpa_learner.rb', line 50

def refine_hypothesis(cex, hypothesis, state_to_prefix)
  tree = @tree
  if tree
    tree.refine_hypothesis(cex, hypothesis, state_to_prefix) # steep:ignore
    return
  end

  @tree =
    DiscriminationTreeVPA.new(
      @alphabet,
      @call_alphabet,
      @return_alphabet,
      @sul,
      cex:,
      cex_processing: @cex_processing
    )
end