Calculates the layer average and the canopy average of leaf properties per layer, per leaf angle and per leaf azimuth (36)

meanleaf averages a leaf-scale property, given as a 3D array over leaf inclination, leaf azimuth and canopy layer, weighted by the leaf inclination distribution function (lidf) and/or a per-layer weight Ps (typically the fraction of sunlit leaf area).

Usage

meanleaf(canopy, F_, canopy.choice, Ps)

Arguments

canopy: list. Canopy structural properties: nlayers (number of canopy layers), nlincl (number of leaf inclination classes), nlazi (number of leaf azimuth classes), lidf (leaf inclination distribution function weights).
F_: numeric array with dimensions (nli, nlazi, nl). Leaf-scale property to average, indexed by leaf inclination class, leaf azimuth class, and canopy layer.
canopy.choice: character. Integration method: 'angles' (integration over leaf angles only, one value per layer), 'layers' (integration over layers only, weighted by Ps, single value), or 'angles_and_layers' (integration over both leaf angles and layers, weighted by lidf and Ps).
Ps: numeric vector of length nl. Fraction of sunlit leaf area per layer, used as the layer weight for canopy.choice %in% c('layers', 'angles_and_layers').

Value

numeric vector. Fout_vertical: for canopy.choice = 'angles', one averaged value per layer (length nl); for 'layers', a single averaged value; for 'angles_and_layers', one averaged value per layer (length nl).

Details

Last update: 7 December 2007; update 11 February 2008 made modular (Joris Timmermans); update 25 Feb 2013 Wout Verhoef: proposed name change, removed globals and used canopy-structure for input.

Author

Christiaan van der Tol (Original version in Matlab)

Carlos Camino (Ported version into R)

Examples

if (FALSE) { # \dontrun{
Fout <- meanleaf(canopy, F_, canopy.choice = 'angles_and_layers', Ps)
} # }