irradiance: Photon (quantum) irradiance from spectral (energy)...

Description Usage Arguments Value Note See Also Examples


This function returns the energy irradiance for a given waveband of a radiation spectrum.


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



numeric Vector of wavelength (nm)


numeric Corresponding vector of spectral (energy) irradiances (W m-2 nm-1)

waveband or list of waveband objects The waveband(s) determine the region(s) of the spectrum that are summarized.


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

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


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


logical Flag indicating whether multiplier values should be cached between calls


logical Flag indicating whether to use hinges to reduce interpolation errors


a single numeric value with no change in scale factor: [W m-2 nm-1] -> [mol s-1 m-2]


The last three parameters control speed optimizations. The defaults should be suitable in mosts cases. If you set check.spectrum=FALSE then you should call check_spectrum() at least once for your spectrum before using any of the other functions. If you will use repeatedly the same SWFs on many spectra measured at exactly the same wavelengths you may obtain some speed up by setting use.cached.mult=TRUE. However, be aware that you are responsible for ensuring that the wavelengths are the same in each call, as the only test done is for the length of the w.length vector. The is no reason for setting use.cpp.code=FALSE other than for testing the improvement in speed, or in cases where there is no suitable C++ compiler for building the package.

See Also

Other irradiance functions: e_fluence, e_irrad, energy_irradiance, fluence, irrad, photon_irradiance, q_fluence, q_irrad


with(, irradiance(w.length, s.e.irrad, new_waveband(400,700), "photon"))

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