two_reflectances

Internal function that computes the two reflectances needed to compute
various waveband ratios and fractions.

internal

Definitions of classes, methods, operators and functions for use
in photobiology and radiation meteorology and climatology. Calculation of
effective (weighted) and not-weighted irradiances/doses, fluence rates,
transmittance, reflectance, absorptance, absorbance and diverse ratios and
other derived quantities from spectral data. Local maxima and minima: peaks,
valleys and spikes. Conversion between energy-and photon-based units.
Wavelength interpolation. Astronomical calculations related solar angles and
day length. Colours and vision. This package is part of the 'r4photobiology'
suite, Aphalo, P. J. (2015) <doi:10.19232/uv4pb.2015.1.14>.

Pedro Aphalo

photobiology

Photobiological Calculations

Pedro J. Aphalo

Titta K. Kotilainen

Glenn Davis

Agnese Fazio

two_reflectances function

<dl><dt>spct</dt>
<dd>an object of class "reflector_spct" or "object_spct".</dd>
<dt>w.band.1, w.band.2</dt>
<dd>waveband objects or lists of waveband objects
used to compute the numerator(s) and denominator(s) of the ratio(s). The
waveband(s) determine the region(s) of the spectrum that are summarized.</dd>
<dt>quantity</dt>
<dd>character string One of "total", "average" or "mean".</dd>
<dt>wb.trim</dt>
<dd>logical if TRUE wavebands crossing spectral data boundaries
are trimmed, if FALSE, they are discarded</dd>
<dt>use.cached.mult</dt>
<dd>logical indicating whether multiplier values should be
cached between calls</dd>
<dt>use.hinges</dt>
<dd>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.</dd>
<dt>naming</dt>
<dd>character one of "long", "default", "short" or "none". Used to
select the type of names to assign to returned value.</dd></dl>

Arguments

Compute two reflectances for ratio, fraction or normalised difference — two_reflectances

<dl>

<dt>spct</dt>
<dd>an object of class "reflector_spct" or "object_spct".</dd>


<dt>w.band.1, w.band.2</dt>
<dd>waveband objects or lists of waveband objects
used to compute the numerator(s) and denominator(s) of the ratio(s). The
waveband(s) determine the region(s) of the spectrum that are summarized.</dd>


<dt>quantity</dt>
<dd>character string One of "total", "average" or "mean".</dd>


<dt>wb.trim</dt>
<dd>logical if TRUE wavebands crossing spectral data boundaries
are trimmed, if FALSE, they are discarded</dd>


<dt>use.cached.mult</dt>
<dd>logical indicating whether multiplier values should be
cached between calls</dd>


<dt>use.hinges</dt>
<dd>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.</dd>


<dt>naming</dt>
<dd>character one of "long", "default", "short" or "none". Used to
select the type of names to assign to returned value.</dd>

</dl>

two_reflectances: Compute two reflectances for ratio, fraction or normalised difference

Description

Usage

Arguments

Details