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Gray-coded genetic algorithm

As explained in Optimization Algorithms: AI techniques for design, planning, and control problems

A genetic algorithm that represents candidate solutions with Gray-coded strings so adjacent numeric values differ in a single bit.

A gray-coded genetic algorithm represents candidate solutions with Gray-coded chromosomes, where adjacent numerical values differ by one bit. This reduces Hamming cliffs: a single crossover or mutation is less likely to cause a large decoded-value jump or premature convergence. section 8.1

A small encoding example

For decimal values 2 and 3, binary codes are 0010 and 0011, while Gray codes are 0011 and 0010. The neighboring values still differ by one bit, illustrating the smoother genotype-to-phenotype mapping. XOR gates can convert 4-bit binary numbers to Gray codes. section 8.1

Table 8.1 Decimal, binary, and Gray coding (view table figure)

Decimal number

Binary code

Gray code

0

0000

0000

1

0001

0001

2

0010

0011

3

0011

0010

4

0100

0110

5

0101

0111

6

0110

0101

7

0111

0100

8

1000

1100

9

1001

1101

10

1010

1111

11

1011

1110

12

1100

1010

13

1101

1011

14

1110

1001

15

1111

1000

Compare decimal values with their binary and Gray representations from 0 through 15. section 8.1

The encoding is useful when binary crossover and mutation can disrupt important high-order bits. It supports smoother search in continuous or discrete optimization settings and appears in applications such as ticket pricing, rotary encoders, and digital-to-analog conversion. section 8.1 section 8.0

How Optimization Algorithms: AI techniques for design, planning, and control problems covers it

How deep it goes
Defines Hamming cliffs, explains adjacent-value encoding, and demonstrates XOR conversion, but does not provide full algorithm pseudocode or parameter guidance.
Examples
Uses a decimal-to-binary-to-Gray table, a ticket-pricing conversion figure, rotary encoders, and digital-to-analog converters.
What you can do after
Evaluate when Gray coding can reduce disruptive binary mutations and crossover effects in genetic-algorithm representations.
How it connects
Connects genetic algorithms with binary encoding, crossover, mutation, fitness landscapes, Hamming distance, and XOR gates.

Related concepts

This explainer was generated by Manning's knowledge graph from the text of Optimization Algorithms: AI techniques for design, planning, and control problems. The section links point to the parts of the book it draws on.