R: Evaluate Covariance and Variogram Functions

RFfctn {RandomFields}

R Documentation

Evaluate Covariance and Variogram Functions

Description

RFfctn returns the values of a shape function.

Usage

RFfctn(model, x, y = NULL, z = NULL, T = NULL, grid, params, distances, dim,...)

Arguments

`model,params`	object of class `RMmodel`, `RFformula` or `formula`; best is to consider the examples below, first. The argument `params` is a list that specifies free parameters in a formula description, see RMformula.
`x`	vector of x coordinates, or object of class `GridTopology` or `raster`; for more options see RFsimulateAdvanced.
`y,z`	optional vectors of y (z) coordinates, which should not be given if `x` is a matrix.
`T`	optional vector of time coordinates, `T` must always be an equidistant vector. Instead of `T=seq(from=From, by=By, len=Len)`, one may also write `T=c(From, By, Len)`.
`grid`	logical; the function finds itself the correct value in nearly all cases, so that usually `grid` need not be given. See also RFsimulateAdvanced.
`distances,dim`	another alternative for the argument `x` to pass the (relative) coordinates, see RFsimulateAdvanced.
`...`	for advanced use: further options and control arguments for the simulation that are passed to and processed by `RFoptions`. If `params` is given, then `...` may include also the variables used in `params`.

Details

RFcovmatrix also allows for variogram models. Then the negative of the variogram matrix is returned.

Value

RFfctn returns a vector.

Author(s)

Martin Schlather, schlather@math.uni-mannheim.de, https://www.wim.uni-mannheim.de/schlather/

Examples

RFoptions(seed=0) ## *ANY* simulation will have the random seed 0; set
##                   RFoptions(seed=NA) to make them all random again

model <- RMexp() - 1
RFfctn(model, 1:10)

[Package RandomFields version 3.3.14 Index]