waveband or list of waveband objects or a numeric vector of
length two. The waveband(s) determine the region(s) of the spectrum that
are summarized. If a numeric range is supplied a waveband object is
constructed on the fly from it.
quantity
character string One of "average" or "mean", "total",
"contribution", "contribution.pc", "relative" or "relative.pc"
wb.trim
logical Flag if wavebands crossing spectral data boundaries
are trimmed or ignored
use.hinges
logical Flag indicating whether to use hinges to reduce
interpolation errors