R: Photon or energy irradiance from spectral energy or photon...

irradiance {photobiology} | R Documentation

## Photon or energy irradiance from spectral energy or photon irradiance.

### Description

Energy or photon irradiance for one or more wavebands of a radiation spectrum.

### Usage

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

### Arguments

`w.length` | numeric Vector of wavelength (nm).
`s.irrad` | numeric vector of spectral (energy) irradiances (W m-2 nm-1).
`w.band` | waveband or list of waveband objects The waveband(s) determine the region(s) of the spectrum that are summarized.
`unit.out` | character 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.

### Value

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

### Note

The last three parameters control speed optimizations. The defaults should be suitable in most 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 low-level functions operating on numeric vectors.: `as_energy`, `as_quantum_mol`, `calc_multipliers`, `div_spectra`, `energy_irradiance`, `energy_ratio`, `insert_hinges`, `integrate_xy`, `interpolate_spectrum`, `l_insert_hinges`, `oper_spectra`, `photon_irradiance`, `photon_ratio`, `photons_energy_ratio`, `prod_spectra`, `s_e_irrad2rgb`, `split_energy_irradiance`, `split_photon_irradiance`, `subt_spectra`, `sum_spectra`, `trim_tails`, `v_insert_hinges`

### Examples

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

[Package photobiology version 0.9.21 Index]