mutation_ga_binary

Arguments

Indiv

A string.

The individual on which we will perform the mutation.

param

a list of parameters.

• "binary_length": an integer scalar, the size of the binary code.

• "multi_mut": a boolean. If %T, several random bits will be flipped.

• "multi_mut_nb": an integer scalar, the number of bits to be flipped. Only used when multi_mut is set to %T (default 2).

Mut_Indiv

A string.

The mutated individual.

pos

A vector of integers.

The positions of the mutated bits.

Description

This function performs a classical multi-bits binary mutation.

This generates the individual Mut_Indiv by inverting bits on random positions.

By default mutation_ga_binary(Indiv) selects randomly an index i between 1 and length(Indiv). It then modifies the i-th character of Indiv to 1 if it was 0, or 0 if it was 1.

If "multi_mut" is set to %T multiple mutations may occur. The maximal number of mutation is given by "multi_mut_nb".

Random number generator

mutation_ga_binary is based on grand for generating the random samples. Use grand("setsd", seed) to change the seed for crossover_ga_binary.

seed = getdate("s");
grand("setsd", seed); //sets the seed to current date

seed = 0;
grand("setsd", seed); //sets the seed to default value

Examples

Indiv="00010000"
[Mut_Indiv, pos] = mutation_ga_binary(Indiv)

// With multiple mutation
param=init_param("multi_mut",%t,"multi_mut_nb",3);
Indiv="00010000"
[Mut_Indiv, pos] = mutation_ga_binary(Indiv,param)

See also

• mutation_ga_default — A continuous variable mutation function
• crossover_ga_binary — A crossover function for binary code
• init_ga_default — A function a initialize a population
• optim_ga — A flexible genetic algorithm