Last data update: 2014.03.03
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R: Ackley test problem
Ackley test problem
Description
Generates the Ackley benchmark function. The Ackley function is a commonly used test problem
for global optimization procedures.
Usage
ackley(x)
Arguments
x |
A matrix containing the values of the input variables.
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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
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")
Results
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