foxleg {RGeoS}R Documentation

Optimize of a set of parameters

Description

Optimize a set of parameters

Usage

foxleg(formula, start = NA, lower = NA, upper = NA, weights = NA, verbose = FALSE)

Arguments

formula

a nonlinear model formula (including variables and parameters) which describes the link between a response variable, some explanatory variables and the parameters to optimize.

start

a named list or named numeric vector of starting estimates. When the initial value is missing for some parameters, they are initialized with a very cheap guess.

lower

a named list or named numeric vector of lower bounds for the set of parameters. If they are not defined for some parameters, the corresponding lower bounds are set to -infinity.

upper

a named list or named numeric vector of upper bounds for the set of parameters. If they are not defined for some parameters, the corresponding lower bounds are set to +infinity.

weights

Set of weights attached to each datum. If not provided, the weights are defaulted to 1

verbose

Verbose flag.

Value

The list containing the optimal values for each parameter.

Examples

# Generate two initial vectors of 100 values (with some randomization)
x <- 2 + rnorm(100)
y <- exp(-0.5 * x) + 0.1 * rnorm(100)
res<- foxleg(y~exp(-a*x)+b)
xp <- seq(-1,6.,0.01)
yp <- exp(-res$a * xp) + res$b
plot(x,y)
lines(xp,yp)

[Package RGeoS version 9.1.1 Index]