wl: Getting and Setting the Wavelength Axis 'wl' returns the...
In hyperSpec: Work with Hyperspectral Data, i.e. Spectra + Meta Information (Spatial, Time, Concentration, ...)

Description Usage Arguments Details Value Note Author(s) See Also Examples

The wavelength axis of a hyperSpec object can be retrieved and replaced with wl and wl<-, respectively.

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wl(x)

wl (x, label=NULL, digits=6) <- value

`x`	a `hyperSpec` object
`label`	The label for the new wavelength axis. See initialize for details.
`digits`	handed to `signif`. See details.
`value`	either a numeric containing the new wavelength vector, or a list with `value$wl` containing the new wavelength vector and `value$label` holding the corresponding `label`.

When the wavelength axis is replaced, the colnames of x@data$spc are replaced by the rounded new wavelengths. digits specifies the how many significant digits should be used.

There are two ways to set the label of the new wavelength axis, see the examples. If no label is given, a warning will be issued.

a numeric vector

hyperSpec object

wl<- always sets the complete wavelength axis, without changing the columns of the spectra matrix. If you rather want to cut the spectral range, use [, for interpolation along the spectral axis see spc.loess and for spectral binning spc.bin.

C. Beleites

signif

cutting the spectral range: [

interpolation along the spectral axis: spc.loess

spectral binning: spc.bin

	wl (laser)

	# convert from wavelength to frequency
	plot (laser)
	wl (laser, "f / Hz") <- 2.998e8 * wl (laser) * 1e9
	plot (laser)

	# convert from Raman shift to wavelength
	# excitation was at 785 nm
	plot (chondro [1])
	wl (chondro) <- list (wl = 1e7 / (1e7/785 - wl (chondro)), label = expression (lambda / nm))
	plot (chondro [1])