Class: Operator::MutationBitRipple

Inherits:
Object
  • Object
show all
Defined in:
../lib/mutation_ripple.rb

Overview

Simple bit-level mutation. It assumes the source genotype has the form of the Array of codons with an interpretation given by CodonMod (see).

Instance Attribute Summary (collapse)

Instance Method Summary (collapse)

Constructor Details

- (MutationBitRipple) initialize(dummy = nil)

Create the mutation operator with default settings. 



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# File '../lib/mutation_ripple.rb', line 12

def initialize dummy=nil
  @random = Kernel
  @codon = CodonMod.new # standard 8-bit codons
end

Instance Attribute Details

- (Object) codon

Codon encoding scheme. By default the instance of the CodonMod class is used (ie. standard GE 8-bit codons) See CodonMod for details. 



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# File '../lib/mutation_ripple.rb', line 19

def codon
  @codon
end

- (Object) random

The source of randomness, used for calling “random.rand( limit )”, defaulting to ‘Kernel’ class. 



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# File '../lib/mutation_ripple.rb', line 22

def random
  @random
end

Instance Method Details

- (Object) mutation(orig, dummy = nil)

Select the random position within the orig vector and mutate it. The resultant value (of a mutated codon) is bit-mutated by self.codon.mutate_bit method. Return the mutated copy of the orig. genotype. 



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# File '../lib/mutation_ripple.rb', line 33

def mutation( orig, dummy=nil )
  mutant = orig.clone
  where = @random.rand( orig.size )
  mutant[ where ] = @codon.mutate_bit( mutant.at(where) )
  mutant
end