TT.chemometrics.alr

Function that compute the additive log-ratio transformation of compositional
data (here texture data). This a a copy-paste-and-rename of the alr function
provided by the package chemometrics: P. Filzmoser and K. Varmuza (2008).
chemometrics: Multivariate Statistical Analysis in Chemometrics. R package
version 0.4. The function has been modified so it returns NA when a value is
below or equal to zero (this happens when using a regular grid of texture
data, for practical reasons). The function has also been modified so it uses
column name rather than column index.

"The Soil Texture Wizard" is a set of R functions designed to produce texture triangles (also called texture plots, texture diagrams, texture ternary plots), classify and transform soil textures data. These functions virtually allows to plot any soil texture triangle (classification) into any triangle geometry (isosceles, right-angled triangles, etc.). This set of function is expected to be useful to people using soil textures data from different soil texture classification or different particle size systems. Many (> 15) texture triangles from all around the world are predefined in the package. A simple text based graphical user interface is provided: soiltexture_gui().

Julien MOEYS

soiltexture

Functions for Soil Texture Plot, Classification and
Transformation

Julien Moeys

Wei Shangguan

Rainer Petzold

Budiman Minasny

Bogdan Rosca

Nic Jelinski

Wiktor Zelazny

Rodolfo Marcondes Silva Souza

Jose Lucas Safanelli

Alexandre ten Caten

TT.chemometrics.alr function

<dl><dt>X</dt>
<dd>A data.frame containing soil texture data</dd>
<dt>divisorvar</dt>
<dd>number of ratioing variable</dd>
<dt>css.names</dt>
<dd>See <code>TT.plot</code></dd></dl>

Arguments

Julien Moeys [aut, cre], Wei Shangguan [ctb], Rainer Petzold [ctb],
Budiman Minasny [ctb], Bogdan Rosca [ctb], Nic Jelinski [ctb], Wiktor
Zelazny [ctb], Rodolfo Marcondes Silva Souza [ctb], Jose Lucas Safanelli
[ctb], Alexandre ten Caten [ctb]

Author

Compute the additive log-ratio transformation of compositional data. — TT.chemometrics.alr

<dl>

<dt>X</dt>
<dd>A data.frame containing soil texture data</dd>


<dt>divisorvar</dt>
<dd>number of ratioing variable</dd>


<dt>css.names</dt>
<dd>See <code>TT.plot</code></dd>

</dl>

TT.chemometrics.alr: Compute the additive log-ratio transformation of compositional data.

Description

Usage

Arguments

Author