| derivcormatrix {CensSpatial} | R Documentation |
First and second derivates of some correlation matrix
Description
It computes the matrix of first and second derivates for the exponential, gaussian, matern, spherical, powered exponential and Cauchy correlation matrix.
Usage
derivcormatrix(coords, phi, kappa = 0, cov.model = "exponential")
Arguments
coords |
2D spatial coordinates. |
phi |
parameter for the matern, powered exponential and cauchy functions. |
kappa |
parameter for all correlation functions. |
cov.model |
parameter correlation funtion to calculates the derivates in this case 6 functions are avalible "exponential", "gaussian", "matern", "spherical", "powered.exponential", "cauchy". |
Details
The correlations functions used to calculate the derivates
from this 6 functions are based in the functions
by the package geoR (see cov.spatial).
Value
H |
distance matrix. |
devR1 |
first derivate of the correlation matrix. |
devR2 |
second derivate of the correlation matrix. |
Author(s)
Alejandro Ordonez <<ordonezjosealejandro@gmail.com>>, Victor H. Lachos <<hlachos@ime.unicamp.br>> and Christian E. Galarza <<cgalarza88@gmail.com>>
Maintainer: Alejandro Ordonez <<ordonezjosealejandro@gmail.com>>
References
Diggle, P. & Ribeiro, P. (2007). Model-Based Geostatistics. Springer Series in Statistics.
Gradshtejn, I. S. & Ryzhik, I. M. (1965). Table of integrals, series and products. Academic Press.
See Also
Examples
n<-200
n1=100
r1=sample(seq(1,30,length=400),n+n1)
r2=sample(seq(1,30,length=400),n+n1)
coords=cbind(r1,r2)
s=derivcormatrix(coords=coords,phi=2,kappa=2,cov.model="exponential")