wrappers {geoR} | R Documentation

## Wrappers for the C functions used in geoR

### Description

These functions are wrappers for some (but not all) the C functions included in the geoR package.
Typically the C code is directly called from the geoR functions but these functions allows independent calls.

### Usage

    diffpairs(coords, data)
    loccoords(coords, locations)
    .diagquadraticformXAX(X, lowerA, diagA)
    .bilinearformXAY(X, lowerA, diagA, Y)
    .corr.diaglowertri(coords, cov.model, phi, kappa)
    .Ccor.spatial(x, phi, kappa, cov.model)

### Arguments

`coords` | an n x 2 matrix with the data coordinates.
`data` | an vector with the data values.
`locations` | an N x 2 matrix with the coordinates of the prediction locations.
`lowerA` | a vector with the diagonal terms of the symmetric matrix A.
`diagA` | a vector with the diagonal terms of the symmetric matrix A.
`X` | a matrix with conforming dimensions.
`Y` | a matrix with conforming dimensions.
`cov.model` | covariance model, see `cov.spatial` for options and more details.
`phi` | numerical value of the correlation function parameter phi.
`kappa` | numerical value of the correlation function parameter kappa.
`x` | a vector of distances.

### Value

The outputs for the different functions are:

`diffpairs` | returns a list with elements `dist` - the distance between pairs of points, and `diff` - the difference between the values of the attributes.
`loccoords` | returns a n x N matrix with distances between data points and prediction locations.
`diagquadraticformXAX` | returns a vector with the diagonal term of the quadratic form t(X) %*% A %*% X.
`bilinearformXAY` | returns a vector or a matrix with the terms of the quadratic form t(X) %*% A %*% Y.
`corr.diaglowertri` | returns the lower triangle of the correlation matrix, including the diagonal.
`Ccor.spatial` | returns a vector of values of spatial correlations.

### Author(s)

Paulo Justiniano Ribeiro Jr. Paulo.Ribeiro@est.ufpr.br,
Peter J. Diggle p.diggle@lancaster.ac.uk.

### References

Further information on the package geoR can be found at:
http://www.est.ufpr.br/geoR.

[Package geoR version 1.5-7 Index]