Class: Wallace::Operators::OnePointCrossoverOperator

Inherits:
Wallace::Operator show all
Defined in:
lib/operators/one_point_crossover_operation.rb

Overview

One-point crossover (also known as single-point crossover) takes two individuals, A and B, as parents, and produces two children, formed by the combination of sub-strings from A and B.

Firstly a single crossover point, common to the two individuals is selected, effectively splitting each parent, A and B, into two substrings (A1, A2; B1, B2). The resulting substrings (A1+B2 and B1+A2) are combined to form two (potentially) unique children.

Instance Method Summary collapse

Methods inherited from Wallace::Operator

#initialize, #produce

Constructor Details

This class inherits a constructor from Wallace::Operator

Instance Method Details

#operate(rng, inputs) ⇒ Object 



11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
 
# File 'lib/operators/one_point_crossover_operation.rb', line 11

def operate(rng, inputs)

  a, b = individuals

  # Ensure that the individuals are longer than length 1!
  return inputs if inputs[0].length <= 1 or inputs[1].length <= 1

  # Calculate the crossover point, split A and B into four substrings
  # and combine those substrings to form two children. 
  x = rng.rand((1...([inputs[0].length, inputs[1].length].min)))
  
  return [
    inputs[0][0...x] + inputs[0][x...inputs[0].length],
    inputs[1][0...x] + inputs[1][x...inputs[1].length]
  ]

end