Class: PropLogic::Variable

Inherits:
Term
  • Object
show all
Defined in:
lib/prop_logic/variable.rb

Direct Known Subclasses

Constant

Instance Attribute Summary

Attributes inherited from Term

#terms

Instance Method Summary collapse

Methods inherited from Term

#and, #assign_false, #assign_true, #each_sat, #equiv?, generate_cache, get, #initialize_copy, #or, #reduce, #sat?, #then, #to_nnf, #to_s_in_term, #unsat?

Methods included from Functions

all_and, all_or, new_variable, sat_loop

Constructor Details

#initialize(name = nil) ⇒ Variable

Returns a new instance of Variable.



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# File 'lib/prop_logic/variable.rb', line 3

def initialize(name = nil)
  @name = name || "v_#{object_id}"
  @terms = [].freeze
  freeze
end

Instance Method Details

#assign(trues, falses, variables = nil) ⇒ Object 



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# File 'lib/prop_logic/variable.rb', line 39

def assign(trues, falses, variables = nil)
  if trues.include? self
    True
  elsif falses.include? self
    False
  else
    self
  end
end

#cnf? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/prop_logic/variable.rb', line 31

def cnf?
  true
end

#nnf? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/prop_logic/variable.rb', line 15

def nnf?
  true
end

#not ⇒ NotTerm Also known as: ~, -@

bypassing Term.get

Returns:



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# File 'lib/prop_logic/variable.rb', line 51

def not
  Term.__send__ :cached, NotTerm, self
end

#reduced? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/prop_logic/variable.rb', line 19

def reduced?
  true
end

#to_cnf ⇒ Object 



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# File 'lib/prop_logic/variable.rb', line 23

def to_cnf
  self
end

#to_s ⇒ Object 



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# File 'lib/prop_logic/variable.rb', line 11

def to_s(*)
  @name
end

#tseitin(pool) ⇒ Object 



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# File 'lib/prop_logic/variable.rb', line 27

def tseitin(pool)
  self
end

#variables ⇒ Object 



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# File 'lib/prop_logic/variable.rb', line 35

def variables
  [self]
end