Class: Lernen::Automaton::MooreLike

Inherits:
TransitionSystem show all
Defined in:
lib/lernen/automaton/moore_like.rb

Overview

MooreLike represents a Moore-like transition system.

This transition system has an output value for each configuration (or state). Therefore, the following invariant is required for all ‘conf` and `input`.

“‘ruby step_output, next_conf = self.step(conf, input) step_output == self.output(next_conf) “`

Note that in this class, the initial output of the ‘#run` method is lost. If it is needed, we can use `#run_empty` instead.

Note that this class is abstract. We should implement the following method:

  • ‘#type`

  • ‘#initial_conf`

  • ‘#step_conf(conf, input)`

  • ‘#output(conf)`

Direct Known Subclasses

DFA, Moore, SPA, VPA

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from TransitionSystem

#initial_conf, random_transition_function, #run, #to_dot, #to_graph, #to_mermaid, #type

Class Method Details

.find_separating_word(alphabet, automaton1, automaton2) ⇒ Object

Finds a separating word between ‘automaton1` and `automaton2`.

: [Conf, In, Out] (

  Array[In] alphabet,
  MooreLike[Conf, In, Out] automaton1,
  MooreLike[Conf, In, Out] automaton2
) -> (Array[In] | nil)



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# File 'lib/lernen/automaton/moore_like.rb', line 72

def self.find_separating_word(alphabet, automaton1, automaton2)
  unless automaton2.is_a?(automaton1.class)
    raise ArgumentError, "Cannot find a separating word for different type automata"
  end

  return [] if automaton1.run_empty != automaton2.run_empty # steep:ignore

  super
end

Instance Method Details

#output(conf) ⇒ Object

Returns the output value for the given configuration.

This is an abstract method.

: (Conf conf) -> Out

Raises:

  • (TypeError) 


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# File 'lib/lernen/automaton/moore_like.rb', line 48

def output(conf)
  raise TypeError, "abstract method: `output`"
end

#run_empty ⇒ Object

Runs and returns the output value of the transitions for the empty string.

: () -> Out



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# File 'lib/lernen/automaton/moore_like.rb', line 63

def run_empty = output(initial_conf)

#step(conf, input) ⇒ Object 



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# File 'lib/lernen/automaton/moore_like.rb', line 55

def step(conf, input)
  next_conf = step_conf(conf, input)
  [output(next_conf), next_conf]
end

#step_conf(conf, input) ⇒ Object

Runs a transition from the given configuration with the given input. It looks like ‘#step`, but it does not return an output value because it can be computed by `#output` in this class.

This is an abstract method.

: (Conf conf, In innput) -> Conf

Raises:

  • (TypeError) 


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# File 'lib/lernen/automaton/moore_like.rb', line 39

def step_conf(conf, input)
  raise TypeError, "abstract method: `step_conf`"
end