Create a spatial covariance parameter object for use with other functions.
Arguments
- spcov_type
The spatial covariance function type. Available options include
"exponential","spherical","gaussian","triangular","circular","cubic","pentaspherical","cosine","wave","jbessel","gravity","rquad","magnetic","matern","cauchy","pexponential","car","sar", and"none".- de
The spatially dependent (correlated) random error variance. Commonly referred to as a partial sill.
- ie
The spatially independent (uncorrelated) random error variance. Commonly referred to as a nugget.
- range
The correlation parameter.
- extra
An extra covariance parameter used when
spcov_typeis"matern","cauchy","pexponential","car", or"sar".- rotate
Anisotropy rotation parameter (from 0 to \(\pi\) radians). A value of 0 (the default) implies no rotation. Not used if
spcov_typeis"car"or"sar".- scale
Anisotropy scale parameter (from 0 to 1). A value of 1 (the default) implies no scaling. Not used if
spcov_typeis"car"or"sar".
Details
Generally, all arguments to spcov_params must be specified, though
default arguments are often chosen based on spcov_type.
When spcov_type is car or
sar, ie is assumed to be 0 unless specified otherwise.
For full parameterizations of all spatial covariance
functions, see spcov_initial().