RFsimulate: Simulation of Random Fields

Description Usage Arguments Details Value Author(s) See Also Examples

Description

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

Usage

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## S4 method for signature 'ANY,Raster'
RFsimulate(model, x,	data=NULL,
 err.model=NULL, n = 1, ...)
## S4 method for signature 'numeric,SpatialGrid'
RFsimulate(model, x,data=NULL,
 err.model=NULL, n = 1, ...)
## S4 method for signature 'numeric,SpatialPixels'
RFsimulate(model, x, data=NULL, 
err.model=NULL, n = 1, ...)
## S4 method for signature 'numeric,SpatialPoints'
RFsimulate(model, x, data=NULL, 
 	err.model=NULL, n = 1, ...)
## S4 method for signature 'numeric,GridTopology'
RFsimulate(model, x, data=NULL, 
 err.model=NULL, n = 1, ...)
## S4 method for signature 'RMmodel,GridTopology'
RFsimulate(model, x, data=NULL, 
 err.model=NULL, n = 1, ...)
## S4 method for signature 'RMmodel,SpatialPoints'
RFsimulate(model, x, data=NULL, 
 err.model=NULL, n = 1, ...)
## S4 method for signature 'matrix,Raster'
RFsimulate(model, x, 	data=NULL, 
 err.model=NULL, n = nrow(model), ...)
## S4 method for signature 'matrix,Spatial'
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 GridTopology or Raster or SpatialPoints or SpatialPixels.

data

For conditional simulation and random imputing only. If data is missing, unconditional simulation is performed.Object of class SpatialPointsDataFrame; 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 RFoptions

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, with the exception of x being a GridTopology where a Raster is returned.

Author(s)

Patrick E. Brown patrick.brown@utoronto.ca

See Also

RFsimulate, RFempiricalvariogram, RFfit, RFgetModelInfo, RFgui, RMmodel, RFoptions, RFsimulateAdvanced, RFsimulate.more.examples

Examples

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


myraster = raster(nrows=20,ncols=30,xmn=0,ymn=0,xmx=6,ymx=4, 
		crs="+init=epsg:2081")

set.seed(0) 

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

plot(simu[['sim2']])

# conditional simulation
firstSample = RFsimulate(
	model, 
	x=SpatialPoints(myraster)[seq(1,ncell(myraster), len=100), ],
	n=3
)

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

plot(secondSample)

# convert the model to RandomFields format and plot
if(requireNamespace('RandomFields', quietly=TRUE)) {
	RandomFields::plot(modelRandomFields(model))
}

geostatsp documentation built on July 20, 2017, 1:02 a.m.