RFsimulate {geostatsp} | R Documentation

## 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,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

    library('geostatsp')
    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))
    }

[Package geostatsp version 1.7.8 Index]