RandomFields (version 3.1.16)

RMcircular: Circular Covariance Model

Description

RMcircular is a stationary isotropic covariance model which is only valid for dimensions $d \le 2 $. The corresponding covariance function only depends on the distance $r \ge 0$ between two points and is given by $$C(r) = 1 - 2/\pi (r \sqrt(1-r^2) + arcsin(r)) 1_{[0,1]}.$$

Usage

RMcircular(var, scale, Aniso, proj)

Arguments

var,scale,Aniso,proj

optional arguments; same meaning for any RMmodel. If not passed, the above covariance function remains unmodified.

Value

RMcircular returns an object of class RMmodel

Details

The model is only valid for dimensions $d \le 2$. It is a covariance function with compact support (cf. Chiles, J.-P. and Delfiner, P. (1999), p. 82).

References

• Chiles, J.-P. and Delfiner, P. (1999) Geostatistics. Modeling Spatial Uncertainty. New York: Wiley.

See Also

RMmodel, RFsimulate, RFfit.

Examples

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

model <- RMcircular()
x <- seq(0, 10, 0.02)
plot(model)
plot(RFsimulate(model, x=x))