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Wavelength-range definition for purple radiation according to ISO or imagers in the Landsat satellites.

Usage

Purple(std = "ISO")

Arguments

std

a character string "ISO", or Landsat imager "LandsatOLI".

Value

A waveband object defining a wavelength range.

Details

Purple (or violet) wavelengths as defined by ISO standards based on human vision overlap the UVA band as defined by a separate ISO standard. In other contexts like plant photobiology purple is included under blue, while some overoptimistic LED sellers call LEDs emitting in the violet region ultraviolet LEDs. In addition to the ISO definition of purple, a purple channel from Landsat imagers is implemented.

See also

new_waveband waveband

Other unweighted wavebands: Blue(), Far_red(), Green(), IR(), Orange(), Red(), UV(), UVA(), UVB(), UVC(), VIS(), Yellow()

Examples

Purple()
#> Purple.ISO 
#> low (nm) 360 
#> high (nm) 450 
#> weighted none 
Purple("ISO")
#> Purple.ISO 
#> low (nm) 360 
#> high (nm) 450 
#> weighted none 

e_irrad(sun.spct, Purple()) # W m-2
#> E_Purple.ISO 
#>     47.75529 
#> attr(,"time.unit")
#> [1] "second"
#> attr(,"radiation.unit")
#> [1] "total energy irradiance"
q_irrad(sun.spct, Purple()) # mol m-2
#> Q_Purple.ISO 
#> 0.0001639893 
#> attr(,"time.unit")
#> [1] "second"
#> attr(,"radiation.unit")
#> [1] "total photon irradiance"
q_irrad(sun.spct, Purple(), scale.factor = 1e6) # umol m-2
#> Q_Purple.ISO 
#>     163.9893 
#> attr(,"time.unit")
#> [1] "second"
#> attr(,"radiation.unit")
#> [1] "total photon irradiance"