photobiology (version 0.12.0)

waveband_ratio: Photon or energy ratio

Description

This function gives the (energy or photon) irradiance ratio between two given wavebands of a radiation spectrum.

Usage

waveband_ratio(
  w.length,
  s.irrad,
  w.band.num = NULL,
  w.band.denom = NULL,
  unit.out.num = NULL,
  unit.out.denom = unit.out.num,
  unit.in = "energy",
  check.spectrum = TRUE,
  use.cached.mult = FALSE,
  use.hinges = getOption("photobiology.use.hinges", default = NULL)
)

Value

a single numeric value giving the ratio

Arguments

w.length

numeric Vector of wavelengths [\(nm\)].

s.irrad

numeric vector of spectral irradiances in [\(W\,m^{-2}\,nm^{-1}\)] or [\(mol\,s^{-1}\,sm^{-2}\,nm^{-1}\)] as indicated by the argument pased to unit.in.

w.band.num, w.band.denom

waveband objects used to compute the numerator and denominator of the ratio.

unit.out.num, unit.out.denom

character Base of expression used to compute the numerator and denominator of the ratio. Allowed values "energy", and "photon", or its alias "quantum".

unit.in

character Allowed values "energy", and "photon", or its alias "quantum".

check.spectrum

logical Flag indicating whether to sanity check input data, default is TRUE.

use.cached.mult

logical Flag indicating whether multiplier values should be cached between calls.

use.hinges

logical Flag indicating whether to insert "hinges" into the spectral data before integration so as to reduce interpolation errors at the boundaries of the wavebands.

Examples

# photon:photon ratio
with(sun.data,
     waveband_ratio(w.length, s.e.irrad,
                    new_waveband(400,500),
                    new_waveband(400,700), "photon"))
# energy:energy ratio
with(sun.data,
     waveband_ratio(w.length, s.e.irrad,
                    new_waveband(400,500),
                    new_waveband(400,700), "energy"))
# energy:photon ratio
with(sun.data,
     waveband_ratio(w.length, s.e.irrad,
                    new_waveband(400,700),
                    new_waveband(400,700),
                    "energy", "photon"))
# photon:photon ratio waveband : whole spectrum
with(sun.data,
     waveband_ratio(w.length, s.e.irrad,
                    new_waveband(400,500),
                    unit.out.num="photon"))
# photon:photon ratio of whole spectrum should be equal to 1.0
with(sun.data,
     waveband_ratio(w.length, s.e.irrad,
     unit.out.num="photon"))