GeoAniso {GeoModels}

Spatial Anisotropy correction

Description

Transforms or back-transforms a set of coordinates according to the geometric anisotropy parameters.

Usage

GeoAniso(coords, anisopars=c(0,1), inverse = FALSE)

Arguments

coords

An n x 2 matrix with the coordinates to be transformed.

anisopars

A bivariate vector with the the anisotropy angle and the anisotropy ratio, respectively. The angle must be given in radians in [0,pi] and the anisotropy ratio must be greater or equal than 1.

inverse

Logical: Default to FALSE. If TRUE the reverse transformation is performed.

Details

Geometric anisotropy is defined by a linear tranformation from the anisotropic space to the isotropic space that is

Y = X R S

where X is a matrix with original coordinates (anisotropic space), and Y is a matrix with transformed coordinates (isotropic space). Here R is a rotation matrix with associated anisotropy angle parameter (in [0,pi]) and a S is a shrinking matrix with associated anisotropy ratio parameter (greeater or equal than one). The two parameters are specified in the anisopars argument as a bivariate numeric vector. The case (.,1) corresponds to the isotropic case.

Value

Returns a matrix of transformed coordinates

Author(s)

Moreno Bevilacqua, [e-mail],https://sites.google.com/view/moreno-bevilacqua/home, Víctor Morales Oñate, [e-mail], https://sites.google.com/site/moralesonatevictor/, Christian", Caamaño-Carrillo, [e-mail],https://www.researchgate.net/profile/Christian-Caamano