RFsimulate {geostatsp}

Simulation of Random Fields

Description

This function simulates conditional and unconditional Gaussian random fields, calling the function in the RandomFields package of the same name.

Usage

## S4 method for signature 'ANY,SpatRaster'
RFsimulate(model, x,	data=NULL,
 err.model=NULL, n = 1, ...)
## S4 method for signature 'numeric,SpatRaster'
RFsimulate(model, x,data=NULL,
 err.model=NULL, n = 1, ...)
## S4 method for signature 'numeric,SpatVector'
RFsimulate(model, x, data=NULL, 
err.model=NULL, n = 1, ...)
## S4 method for signature 'RMmodel,SpatRaster'
RFsimulate(model, x, data=NULL, 
 err.model=NULL, n = 1, ...)
## S4 method for signature 'RMmodel,SpatVector'
RFsimulate(model, x, data=NULL, 
 err.model=NULL, n = 1, ...)
## S4 method for signature 'matrix,SpatRaster'
RFsimulate(model, x, 	data=NULL, 
 err.model=NULL, n = nrow(model), ...)
## S4 method for signature 'matrix,SpatVector'
RFsimulate(model, x,	data=NULL, 
	err.model=NULL, n = nrow(model), ...)
## S4 method for signature 'data.frame,ANY'
RFsimulate(model, x,	data=NULL, 
	err.model=NULL, n = nrow(model), ...)
modelRandomFields(param, includeNugget=FALSE)

Arguments

model

object of class RMmodel, a vector of named model parameters, or a matrix where each column is a model parameter

x

Object of type SpatRaster or SpatVector.

data

For conditional simulation and random imputing only. If data is missing, unconditional simulation is performed. Object of class SpatVector; coordinates and response values of measurements in case that conditional simulation is to be performed

err.model

For conditional simulation and random imputing only.
Usually err.model=RMnugget(var=var), or not given at all (error-free measurements).

n

number of realizations to generate.

...

for advanced use: further options and control parameters for the simulation that are passed to and processed by RFoptionsin the RandomFieldspackage

param

A vector of named parameters

includeNugget

If FALSE, the nugget parameter is ignored.

Details

If model is a matrix, a different set of parameters is used for each simulation. If data has the same number of columns as model has rows, a different column i is used with parameters in row i.

Value

An object of the same class as x.

Author(s)

Patrick E. Brown [e-mail]

See Also

RFsimulatein the RandomFieldspackage

Examples

library('geostatsp')

# exclude this line to use the RandomFields package
options(useRandomFields = FALSE)

model1 <- c(var=5, range=1,shape=0.5)


myraster = rast(nrows=20,ncols=30,extent = ext(0,6,0,4), 
	crs="+proj=utm +zone=17 +datum=NAD27 +units=m +no_defs")

set.seed(0) 

simu <- RFsimulate(model1, x=myraster, n=3)

plot(simu[['sim2']])

xPoints = suppressWarnings(as.points(myraster))
# conditional simulation
firstSample = RFsimulate(
	c(model1, nugget=1), 
	x=xPoints[seq(1,ncell(myraster), len=100), ],
	n=3
)

secondSample = RFsimulate(
	model = cbind(var=5:3, range=seq(0.05, 0.25, len=3), shape=seq(0.5, 1.5, len=3)),
  err.model = 1,
	x= myraster,
	data=firstSample,n=4
)

plot(secondSample)