R: Cross-Validation of Classical PCA Results for a Spectra...

cv_pcaSpectra {ChemoSpec}

R Documentation

Cross-Validation of Classical PCA Results for a Spectra Object

Description

This function carries out classical PCA on the data in a Spectra object using a cross-validation method. A simple re-write of Peter Filzmoser's pcaCV method with some small plotting changes.

Usage

cv_pcaSpectra(spectra, pcs, choice = "noscale", repl = 50, segments = 4,
  segment.type = c("random", "consecutive", "interleaved"), length.seg,
  trace = FALSE, ...)

Arguments

`spectra`	An object of S3 class `Spectra`.
`pcs`	As per `pcaCV` where it is called amax; an integer giving the number of PC scores to include.
`choice`	A character string indicating the choice of scaling. One of `c("noscale"`, `"autoscale"`, `"Pareto")`.
`repl`	As per `pcaCV`; the number of replicates to perform.
`segments`	As per `pcaCV`.
`segment.type`	As per `pcaCV`.
`length.seg`	As per `pcaCV`.
`trace`	As per `pcaCV`.
`...`	Parameters to be passed to the plotting routines.

Value

A list as described in pcaCV, so the result must be assigned or it will appear at the console. Side effect is a plot.

Author(s)

Bryan A. Hanson, DePauw University. Derived from pcaCV.

References

K. Varmuza and P. Filzmoser Introduction to Multivariate Statistical Analysis in Chemometrics, CRC Press, 2009.

https://github.com/bryanhanson/ChemoSpec

Examples


data(SrE.IR)
pca <- cv_pcaSpectra(SrE.IR, pcs = 5)

[Package ChemoSpec version 4.4.97 Index]