ackley: Ackley test problem

Description Usage Arguments Value Author(s) References Examples

View source: R/ackley.R

Description

Generates the Ackley benchmark function. The Ackley function is a commonly used test problem for global optimization procedures.

Usage

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ackley(x)

Arguments

x

A matrix containing the values of the input variables.

Value

Vector of the same length as x giving the values of the Ackley function.

Author(s)

Laura Villanova, Kate Smith-Miles and Rob J Hyndman

References

http://www-optima.amp.i.kyoto-u.ac.jp/member/student/hedar/Hedar_files/TestGO_files/Page295.htm

Examples

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x1 <- seq(-2, 2, length = 50)
x2 <- x1

x <- expand.grid(x1, x2)

z <- matrix(ackley(x),nrow = length(x1))

nrz <- nrow(z)
ncz <- ncol(z)
jet.colors <- colorRampPalette( c("red", "yellow") ) 
nbcol <- 100
color <- jet.colors(nbcol)
zfacet <- z[-1, -1] + z[-1, -ncz] + z[-nrz, -1] + z[-nrz, -ncz]
facetcol <- cut(zfacet, nbcol)

persp(x1, x2, z, col = color[facetcol], theta = 0, phi = 10, 
	expand = 1, xlab = "x1", ylab = "x2", zlab = "f(x1, x2)", 
	ticktype = "detailed")

Example output

Loading required package: earth
Loading required package: plotmo
Loading required package: plotrix
Loading required package: TeachingDemos
Loading required package: clusterSim
Loading required package: cluster
Loading required package: MASS

This is package 'modeest' written by P. PONCET.
For a complete list of functions, use 'library(help = "modeest")' or 'help.start()'.

Warning messages:
1: In rgl.init(initValue, onlyNULL) : RGL: unable to open X11 display
2: 'rgl_init' failed, running with rgl.useNULL = TRUE 
3: .onUnload failed in unloadNamespace() for 'rgl', details:
  call: fun(...)
  error: object 'rgl_quit' not found 

emma documentation built on May 2, 2019, 2:47 p.m.