R: Spectra Objects

Spectra {ChemoSpec} | R Documentation

## Spectra Objects

### Description

In `ChemoSpec`, spectral data sets are stored in an S3 class called `Spectra`, which contains a variety of information in addition to the spectra themselves. `Spectra` objects are created by `files2SpectraObject` or `matrix2SpectraObject`.

### Structure

The structure of a `Spectra` object is a list of 7 elements and an attribute as follows:

element | type | description
$freq | num | A common frequency (or wavelength) axis for all the spectra.
$data | num | The intensities for the spectra. A matrix of dimension
|  | no. samples x no. frequency points.
$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 | chr | The colors for each sample; length must be no. samples.
|  | Groups and colors correspond.
$sym | integer | As for `colors`, but symbols for plotting (if b/w is desired).
$alt.sym | chr | Lower-case letters as alternate symbols for plotting.
$unit | chr | Two entries, the first giving the x axis unit, the second the y axis unit.
$desc | chr | A character string describing the data set. This appears on plots and therefore
|  | should probably be kept to 40 characters or less.
- attr | chr "Spectra" | The S3 class designation.

### Author(s)

Bryan A. Hanson, DePauw University.

### References

https://github.com/bryanhanson/ChemoSpec

### See Also

`sumSpectra` to summarize a `Spectra` object. `sumGroups` to summarize group membership of a `Spectra` object. `chkSpectra` to verify the integrity of a `Spectra` object. `colorSymbol` for a discussion of color options.

[Package ChemoSpec version 4.4.97 Index]