evaluateLAD: Evaluate the function values of a leaf area distribution

In zhaokg/hemiphoto2LAI: Estimation of Leaf Area Index and Leaf Angle Distribution from Hemispherical Photos

Description

Compute the curve or function values of a chosen LAD

Usage

   evaluateLAD(ladType, ladParameter, option=list(),...) 

Arguments

ladType	a three-leter string to specify one of the 19 LAD models supported (e.g., "es1","uni",and "lan"). Type print(LAD_list) to see more details about all the 19 possible LAD models.
ladParameter	a vector of two elements specifying the parameter values of the chosen LAD type ladType. NAs should be filled if the LAD model is parameter-free or has just one parameter. Type print(LAD_list) to get more information about the valid parameter ranges for the 19 LAD models.
option	(optional). If absent, evaluateLAD will use default model parameters. If option is present, it must be a list variable consiting of two elements: "option$scaledParameter" as a binary variable being either 1 or 0 to indicate how to interpret the second argument ladParameter; "option$N" to specify how many annuli will the zenith range be divided into in evaluation of the LAD.
...	additional parameters, not used currently but reserved for future extension

Value

The output is a LIST object,comprising the following elements:

THETA	a vector of length option$N x 1, which is the locations of zenith angles at which the LAD will be evalauted.
G	a vector of length option$N x 1, giving the evaluted LAD values at the angles of THETA.
PAR	a copy of the input LAD parameters.

References

Zhao et al. (2019). How to better estimate leaf area index and leaf angle distribution from digital hemispherical photography? Switching to a binary nonlinear regression paradigm (under review)

Examples

library(hemiphoto2LAI)

#--------------------------------Example 1--------------------------------#
opt=list()             #Create an empty list to append individual parameters
opt$N=100              #The full zenith range (i.e, [0, pi/2]) divided into 
                       #100 intervals
opt$scaledParameter=0  #If set to 0, the ladParamter input should be valid values  
                       #falling within the expected range of the chosen LAD. If set
                       # to 1, ladParamter is two numbers within [0, 1] to 
                       # be scaled to the valid ranges of the chosen LAD model.
result=simHemiphoto("es1", c(0.1, NA), opt)
#*****************************End of Example 1****************************#
 

zhaokg/hemiphoto2LAI documentation built on July 26, 2019, 9:36 a.m.