GA: ga_pmutation – R documentation

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ga_pmutation

Variable mutation probability in genetic algorithms

Description

A function which calculates the mutation probability for the current iteration. This enables to use GAs with variable mutation rate (see examples).

Usage

ga_pmutation(object, p0 = 0.5, p = 0.01, T = round(object@maxiter/2), ...)

Arguments

`object`	An object of class `"ga"`, usually resulting from a call to function `ga`.
`p0`	initial probability of mutation.
`p`	limiting probability of mutation.
`T`	maximum iteration after which it should converges to `p`.
`...`	Further arguments passed to or from other methods.

Value

Return a numeric value in the range (0,1).

Author(s)

Luca Scrucca

Examples

## Not run: 
Rastrigin <- function(x1, x2)
{
  20 + x1^2 + x2^2 - 10*(cos(2*pi*x1) + cos(2*pi*x2))
}

GA <- ga(type = "real-valued", 
         fitness =  function(x) -Rastrigin(x[1], x[2]),
         lower = c(-5.12, -5.12), upper = c(5.12, 5.12), 
         popSize = 50, maxiter = 500, run = 100,
         pmutation = ga_pmutation)
plot(GA)

GA <- ga(type = "real-valued", 
         fitness =  function(x) -Rastrigin(x[1], x[2]),
         lower = c(-5.12, -5.12), upper = c(5.12, 5.12), 
         popSize = 50, maxiter = 500, run = 100,
         pmutation = function(...) ga_pmutation(..., p0 = 0.1))
plot(GA)

## End(Not run)

GA

Genetic Algorithms

v3.2.1

GPL (>= 2)

Authors

Luca Scrucca [aut, cre] (<https://orcid.org/0000-0003-3826-0484>)

Initial release

2021-04-20