ChemoSpec2D: Spectra2D – R documentation

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Spectra2D

Spectra2D Objects

Description

In ChemoSpec2D, spectral data sets are stored in an S3 class called Spectra2D, which contains a variety of information in addition to the spectra themselves. Spectra2D objects are created by files2Spectra2DObject.

Structure

The structure of a Spectra2D object is a list of eight elements and an attribute as follows: w

element	type	description
$F2	num	A common frequency (or wavelength) axis corresponding
		to the F2 dimension in NMR or the x axis more generally.
		Must be sorted ascending.
$F1	num	A common frequency (or wavelength) axis corresponding
		to the F1 dimension in NMR or the y axis more generally.
		Must be sorted ascending.
$data	num	A list of matrices. Each matrix contains a 2D spectrum.
		Each matrix should have `length(F1)` rows and
		`length(F2)` columns. The matrix must not have dimnames.
		The low end of the F2 dimension is last column of the last row
		(lower right hand corner as typically displayed). The low end of
		the F1 dimension is the last column of the first row (upper right hand corner).
		In other words, the spectrum is stored as typically displayed.
		The list of matrices, if named, should have the same names as
		`names`. However, this is not currently enforced.
$names	chr	The sample names for the spectra; length must be no. samples.
$groups	factor	The group classification of the samples; length must be no. samples.
$colors	character	Colors for plotting; length must be no. samples.
		Colors correspond to groups.
$units	chr	Three entries, the first giving the F2 (x) axis unit, the
		second the F1 (y) axis unit, and the third the z axis unit,
		usually some kind of intensity.
$desc	chr	A character string describing the data set.
- attr	chr	"Spectra2D" The S3 class designation.

Author(s)

Bryan A. Hanson, DePauw University.

Examples

data(MUD1)
str(MUD1)
sumSpectra(MUD1)

ChemoSpec2D

Exploratory Chemometrics for 2D Spectroscopy

v0.4.187

GPL-3

Authors

Bryan A. Hanson [aut, cre] (<https://orcid.org/0000-0003-3536-8246>)

Initial release

2021-03-15