R: Default function to create fixed matrix part of spatial...

Krig.null.function {fields} | R Documentation

## Default function to create fixed matrix part of spatial process model.

### Description

Constructs a matrix of terms representing a low order polynomial and binds additional columns due to covariates ( the Z matrix)

### Usage

    Krig.null.function(x, Z = NULL, drop.Z = FALSE, m)

### Arguments

`x` | Spatial locations
`Z` | Other covariates to be associated with each location.
`drop.Z` | If TRUE only the low order polynomial part is created.
`m` | The polynomial order is (m-1).

### Details

This function can be modified to produce a different fixed part of the spatial model. The arguments x, Z and drop.Z are required but other arguments can be passed as part of a list in null.args in the call to Krig.

### Value

A matrix where the first columns are the polynomial terms and the following columns are from Z.

### Author(s)

Doug Nychka

### See Also

Krig

[Package fields version 9.6.1 Index]