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 3.3.1

Index]