ilr: [!] Isometric logratio transformation

In GegznaV/spHelper: Extension of Package `hyperSpec` and Various Convenience Functions

[!] Isometric logratio transformation

Description

Compute the isometric log ratio transform of a (dataset of) composition(s). Default method is function ilr from package compositions.

Usage

ilr(x, V = ilrBase(x), ...)

## Default S3 method:
ilr(x, V = ilrBase(x), ...)

## S3 method for class 'hyperSpec'
ilr(x, V = ilrBase(x), ...)

Arguments

x	A composition, not necessarily closed. (A numeric data frame or matrix.)
...	further parameters to ilr.

Value

Returns the transformed data matrix with one dimension less than x. Thus for hyperSpec object the last value of x$.wavelength is removed.

See Also

ilr, ilrBase

Other row-wise transformations: alr(), apt(), clr(), cpt(), ipt()

Examples

library(spHelper)
data("Spectra2")
ilr(Spectra2)

plot(Spectra2)
plot(ilr(Spectra2))

GegznaV/spHelper documentation built on April 16, 2023, 1:42 p.m.