Arguments
M
number of centroids in x-direction
N
number of centroids in y-direction
spatial
an object of class spatialAtRisk
sigma
scaling paramter for spatial covariance function, see Brix and Diggle (2001)
phi
scaling paramter for spatial covariance function, see Brix and Diggle (2001)
model
correlation type see ?CovarianceFct
covpars
vector of additional parameters for certain classes of covariance function (eg Matern), these must be supplied in the order given in ?CovarianceFct