CODING FOR GENETIC ALGORITHMS

Sushil J. Louis
Computer Science Department
University of Nevada, Reno

Binary encodings, One parameter

Example:

In the range [0 .. 31]

Easy

In the range [0 .. 50]

How do you do this?

One parameter

In general: X ranges from

How many bits do you need?

How do you decode?

b bit string needs to be converted to a number between and

b bit string defines distinct values

b bit string decodes to val

Decoded value:

One parameter

In general: X ranges from

How many bits do you need?

Mapping [... ] to

What is the precision?

Precision is

0000..00 =

0000..01 = + precision

0000..10 = + precision * 2

Example:

• X = [0...6]
• Needs 3 bits at least
• 011 = ?
• 
• 100 = ?
• 
• 000 = ?
• 
• 111 = ?
• 

Encoding Many Parameters

Suppose we have n parameters

Encode each parameter in a binary string

Concatenate encoded parameters to form a chromosome

Decoding Many Parameters

1. Decode each parameter
2. Calculate function value

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