hyperSpec (version 0.98-20140523)

wl: Getting and Setting the Wavelength Axis wl returns the wavelength axis, wl<- sets it.

Description

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

Usage

wl(x)
  wl (x, label=NULL, digits=6, short="wl<-", user = NULL,
    date = NULL) <- value

Arguments

x

a hyperSpec object

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.

label

The label for the new wavelength axis. See initialize for details.

digits

handed to signif. See details.

short,user,date

deprecated.

Value

• a numeric vector

  hyperSpec object

Details

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.

See Also

signif

cutting the spectral range: [

interpolation along the spectral axis: spc.loess

spectral binning: spc.bin

Examples

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])