make.gmCompositionalGaussianSpatialModel: Construct a Gaussian gmSpatialModel for regionalized...

In gmGeostats: Geostatistics for Compositional Analysis

Construct a Gaussian gmSpatialModel for regionalized compositions

Description

Construct a regionalized compositional data container to be used for Gaussian-based geostatistics: variogram modelling, cokriging and simulation.

Usage

make.gmCompositionalGaussianSpatialModel(
  data,
  coords = attr(data, "coords"),
  V = "ilr",
  prefix = NULL,
  model = NULL,
  beta = model$beta,
  formula = model$formula,
  ng = NULL,
  nmax = ng$nmax,
  nmin = ng$nmin,
  omax = ng$omax,
  maxdist = ng$maxdist,
  force = ng$force
)

Arguments

data	either a compositions::acomp() compositional data set, or else a sp::SpatialPointsDataFrame() containing it
coords	the coordinates of the sampling locations, if no SpatialPointsDataFrame was provided
V	optionally, a matrix of logcontrasts, or else one of the following strings: "alr", "ilr" or "clr"; to produce a plot of the empirical variogram in the corresponding representation; default to variation-variograms
prefix	the desired prefix name for the logratio variables, if this is wished to be forced; otherwise derived from V
model	a variogram model, of any relevant class
beta	(see formula) the coefficients of dependence of the mean of the random field, if these are known; e.g. if formula=~1 constant mean, and the mean is indeed known, beta would be a compositional mean; seldom used directly
formula	a formula without left-hand-side term, e.g. ~1 or ~Easting+Northing, specifying what do we know of the dependence of the mean of the random field; this follows the same ideas than in gstat::gstat()
ng	optional neighborhood information, typically created with KrigingNeighbourhood()
nmax	optional, neighborhood description: maximum number of data points per cokriging system
nmin	optional, neighborhood description: minimum number of data points per cokriging system
omax	optional, neighborhood description: maximum number of data points per cokriging system per quadrant/octant
maxdist	optional, neighborhood description: maximum radius of the search neighborhood
force	optional logical, neighborhood description: if not nmin points are found inside maxdist radius, keep searching. This and all preceding arguments for neighborhood definition are borrowed from gstat::gstat()

Value

A "gmSpatialModel" object with all information provided appropriately structured. See gmSpatialModel.

See Also

SequentialSimulation(), TurningBands() or CholeskyDecomposition() for specifying the exact simulation method and its parameters, predict_gmSpatialModel for running predictions or simulations

Other gmSpatialModel: Predict(), as.gmSpatialModel(), gmSpatialModel-class, make.gmCompositionalMPSSpatialModel(), make.gmMultivariateGaussianSpatialModel()

Examples

data("jura", package="gstat")
X = jura.pred[1:20,1:2]
Zc = compositions::acomp(jura.pred[1:20,7:13])
make.gmCompositionalGaussianSpatialModel(data=Zc, coords=X, V="alr")

gmGeostats documentation built on Aug. 21, 2025, 5:43 p.m.