Package 'RLeafAngle'

Title: Estimates, Plots and Evaluates Leaf Angle Distribution Functions, Calculates Extinction Coefficients
Description: Leaf angle distribution is described by a number of functions (e.g. ellipsoidal, Beta and rotated ellipsoidal). The parameters of leaf angle distributions functions are estimated through different empirical relationship. This package includes estimations of parameters of different leaf angle distribution function, plots and evaluates leaf angle distribution functions, calculates extinction coefficients given leaf angle distribution. Reference: Wang(2007)<doi:10.1016/j.agrformet.2006.12.003>.
Authors: Wei-Min Wang <[email protected]>
Maintainer: Wei-Min Wang <[email protected]>
License: GPL
Version: 1.0
Built: 2025-03-03 04:32:41 UTC
Source: https://github.com/cran/RLeafAngle

Help Index


Compute the Beta distribution of leaf zenith angle.

Description

Compute the Beta distribution of leaf zenith angle.

Usage

BetaDis(meu, neu)

Arguments

meu

One of the parameters for Beta function.

neu

One of the parameters for Beta function.

Value

The Beta distribution of leaf zenith angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

sDis<-BetaDis(1.616,2.188)
plot(c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5), sDis, 
xlab=expression(Leaf~zenith~angle~~(""^"o")), ylab="Leaf area freqency")

Compute the parameter of Beta function given leaf angle distribution mearuements.

Description

Compute the parameter of Beta function given leaf angle distribution mearuements.

Usage

computeBeta(LeafAngles)

Arguments

LeafAngles

The measurements of leaf angle distribution.

Value

The two parameters of Beta function given leaf angle distribution mearuements.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

data(Pisek)
computeBeta(Pisek[[2]])

Compute the mean projection of unit leaf area on the plane perpendicular to beam direction, namely, G parameter.

Description

Compute the mean projection of unit leaf area on the plane perpendicular to beam direction, namely, G parameter.

Usage

computeG(LeafAngleZ, FractionZ, LeafAngleA, FractionA, theta, alpha)

Arguments

LeafAngleZ

The center angles list of leaf zenith angle intervals.

FractionZ

The leaf area fraction list given leaf zenith angle intervals list.

LeafAngleA

The center angles list of leaf azimuth angle intervals.

FractionA

The leaf area fraction list given leaf azimuth angle intervals list.

theta

The zenith angle of beam direction.

alpha

The azimuth angle of beam direction.

Value

The mean projection of unit leaf area on the plane perpendicular to beam direction, namely, G value.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

angleZ<-c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5)
angleA<-c(10,30,50,70,90,110,130,150,170,190,210,230,250,270,290,310,330,350)
sADis<-sysAziDis()
sZDis<-sphericalDis()
for(solarZenith in 10:80)
{
  print(computeG(angleZ,sZDis,angleA,sADis,solarZenith,40))
}

Compute the G value given lamda (the parameter of ellipsoidal function) and beam direction.

Description

Compute the G value given lamda (the parameter of ellipsoidal function) and beam direction.

Usage

computeGEllip(lambda, theta)

Arguments

lambda

The parameter of ellipsoidal function given leaf angle distribution mearuements.

theta

The zenith angle of beam direction.

Value

The G value.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

computeGEllip(1.0, 30)

Compute the parameter of ellipsoidal function given leaf angle distribution mearuements.

Description

Compute the parameter of ellipsoidal function given leaf angle distribution mearuements.

Usage

computeLambda(LeafAngles)

Arguments

LeafAngles

The measurements of leaf angle distribution.

Value

The parameter of ellipsoidal function given leaf angle distribution mearuements.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

data(Pisek)
computeLambda(Pisek[[2]])

Compute the parameter of rotated-ellipsoidal function given leaf angle distribution mearuements.

Description

Compute the parameter of rotated-ellipsoidal function given leaf angle distribution mearuements.

Usage

computeLambdaR(LeafAngles)

Arguments

LeafAngles

The measurements of leaf angle distribution.

Value

The parameter of ellipsoidal function given leaf angle distribution mearuements.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

data(Pisek)
computeLambdaR(Pisek[[2]])

Compute the fraction of sunlit folige given solar position, LAI and G value with the assumption of the symmetric distribution of leaf azimuth angle.

Description

Compute the fraction of sunlit folige given solar position, LAI and G value with the assumption of the symmetric distribution of leaf azimuth angle.

Usage

computeSunlit(Theta, G, LAI)

Arguments

Theta

Solar zenith angle.

G

The G value, namely the projection of foliage area.

LAI

Leaf area index.

Value

The fraction of sunlit foliage.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

computeSunlit(30, 0.5, 2.0)

Compute the parameter of Verhoef's leaf angle distribution given leaf angle mearuements.

Description

Compute the parameter of Verhoef's leaf angle distribution given leaf angle distribution mearuements.

Usage

computeTrig(LeafAngles)

Arguments

LeafAngles

The measurements of leaf angle distribution.

Value

The two parameters of Verhoef's leaf angle distribution.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

data(Pisek)
computeTrig(Pisek[[2]])

Compute the ellipsoidal distribution of leaf zenith angle.

Description

Compute the ellipsoidal distribution of leaf zenith angle.

Usage

ellipsoidalDis(lambda)

Arguments

lambda

The parameter of ellipsoidal function.

Value

The ellipsoidal distribution of leaf zenith angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

sDis<-ellipsoidalDis(1)
plot(c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5), sDis, 
xlab=expression(Leaf~zenith~angle~~(""^"o")), ylab="Leaf area freqency")

Compute the rotated ellipsoidal distribution of leaf zenith angle.

Description

Compute the rotated ellipsoidal distribution of leaf zenith angle.

Usage

ellipsoidalRDis(lambdaR)

Arguments

lambdaR

The parameter of rotated-ellipsoidal function.

Value

The rotated ellipsoidal distribution of leaf zenith angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

sDis<-ellipsoidalRDis(1)
plot(c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5), sDis, 
xlab=expression(Leaf~zenith~angle~~(""^"o")), ylab="Leaf area freqency")

Estimate the parameters of Beta distribution given leaf angle measurements.

Description

Estimate the parameters of Beta distribution given leaf angle measurements.

Usage

estBeta(LeafAngles)

Arguments

LeafAngles

The leaf angle measurements.

Value

the parameters of Beta distribution.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

angleZ<-c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5)
angleA<-c(10,30,50,70,90,110,130,150,170,190,210,230,250,270,290,310,330,350)
sADis<-sysAziDis()
sZDis<-sphericalDis()
for(solarZenith in 10:80)
{
  print(computeG(angleZ,sZDis,angleA,sADis,solarZenith,40))
}

Compute the extremophile distribution of leaf zenith angle.

Description

Compute the extremophile distribution of leaf zenith angle.

Usage

extremophileDis()

Value

The extremophile distribution of leaf zenith angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

sDis<-extremophileDis()
plot(c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5), sDis, 
xlab=expression(Leaf~zenith~angle~~(""^"o")), ylab="Leaf area freqency")

Leaf angle distribution measurements provided by D.S. Falster

Description

Leaf angle distribution data measured in two sites of Ku-ringgai Chase National Park, Sydney, Australia and provided by Dr. D.S. Falster of Macquarie University, Australia

Usage

data(Falster)

Format

A list with 39 arrays where one array for tree specy name and 38 array of leaf angle distribution for each specy.

Details

Leaf angle distribution measurements provided by D.S. Falster

Author(s)

W.-M. Wang (wmwangATgmail.com)

Source

Falster, D. and Westoby, M., 2003. Leaf size and angle vary widely across species: what consequences for light interception? New Phytol.158, 509-525.

Examples

data(Falster) 
Falster[1]

Compute the fraction leaf area given leaf angle intervals (in degree) and the parameters of Beta function.

Description

Compute the fraction leaf area given leaf angle intervals (in degree) and the parameters of Beta function.

Usage

interBeta(AngleLower, AngleUpper, meu, neu)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

meu

One of the parameters for Beta function.

neu

One of the parameters for Beta function.

Value

Compute the fraction leaf area of Beta function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interBeta(40,50,1.616,2.188)

Compute the fraction leaf area given leaf angle intervals (in degree) and the parameters of ellipsoidal function.

Description

Compute the fraction leaf area given leaf angle intervals (in degree) and the parameters of ellipsoidal function.

Usage

interEllip(AngleLower, AngleUpper, lambda)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

lambda

The parameter of ellipsoidal function.

Value

Compute the fraction leaf area of ellipsoidal function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interEllip(40,50,1.1)

Compute the fraction leaf area for rotated-ellipsoidal function given leaf angle intervals (in degree) and the parameters.

Description

Compute the fraction leaf area given leaf angle intervals (in degree) and the parameters of rotated-ellipsoidal function.

Usage

interEllipR(AngleLower, AngleUpper, lambdaR)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

lambdaR

The parameter of rotated-ellipsoidal function.

Value

Compute the fraction leaf area of rotated-ellipsoidal function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interEllipR(40,50,1.1)

Compute the fraction leaf area of Erectophile distribution given leaf angle intervals (in degree).

Description

Compute the fraction leaf area of Erectophile distribution given leaf angle intervals (in degree).

Usage

interErectophile(AngleLower, AngleUpper)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

Value

Compute the fraction leaf area of Erectophile function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interErectophile(40,50)

Compute the fraction leaf area of Extremophile distribution given leaf angle intervals (in degree).

Description

Compute the fraction leaf area of Extremophile distribution given leaf angle intervals (in degree).

Usage

interExtremophile(AngleLower, AngleUpper)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

Value

Compute the fraction leaf area of Extremophile function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interExtremophile(40,50)

Compute the fraction leaf area of Plagiophile distribution given leaf angle intervals (in degree).

Description

Compute the fraction leaf area of Plagiophile distribution given leaf angle intervals (in degree).

Usage

interPlagiophile(AngleLower, AngleUpper)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

Value

Compute the fraction leaf area of Plagiophile function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interPlagiophile(40,50)

Compute the fraction leaf area of Planophile distribution given leaf angle intervals (in degree).

Description

Compute the fraction leaf area of Planophile distribution given leaf angle intervals (in degree).

Usage

interPlanophile(AngleLower, AngleUpper)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

Value

Compute the fraction leaf area of Planophile function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interPlanophile(40,50)

Compute the fraction leaf area of Spherical function given leaf angle intervals (in degree).

Description

Compute the fraction leaf area of Spherical function given leaf angle intervals (in degree).

Usage

interSpherical(AngleLower, AngleUpper)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

Value

Compute the fraction leaf area of Spherical function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interSpherical(40,50)

Compute the fraction leaf area of Uniform distribution given leaf angle intervals (in degree).

Description

Compute the fraction leaf area of Uniform distribution given leaf angle intervals (in degree).

Usage

interUniform(AngleLower, AngleUpper)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

Value

Compute the fraction leaf area of Uniform function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

interUniform(40,50)

Compute the fraction leaf area given leaf angle intervals (in degree) and the parameters of Verhoef's leaf angle distribution function.

Description

Compute the fraction leaf area given leaf angle intervals (in degree) and the parameters of Verhoef's leaf angle distribution function.

Usage

intervalTrig(AngleLower, AngleUpper, ap, bp)

Arguments

AngleLower

The lower limit of leaf angle intervals in degree.

AngleUpper

The upper limit of leaf angle intervals in degree.

ap

One of the parameters of Verhoef's leaf angle distribution function.

bp

One of the parameters of Verhoef's leaf angle distribution function.

Value

Compute the fraction leaf area of Verhoef's leaf angle distribution function.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

intervalTrig(40,50, -0.325, -0.173)

Retrieve the density of leaf area given leaf angle measurements.

Description

Retrieve the density of leaf area given leaf angle measurements.

Usage

LADdensity(LeafAngles)

Arguments

LeafAngles

The measurements of leaf angle distribution.

Value

Leaf area density given leaf angle intervals (0,10,20,30,40,50,60,70,80,90).

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

data(Falster) 
LADdensity(Falster[[2]])

Leaf angle distribution measurements provided by Jan Pisek

Description

Leaf angle distribution data provided by Dr. Tartu Observatory, Department of Remote Sensing, Estonia

Usage

data(Pisek)

Format

A list with 55 arrays where one array for tree specy name and 54 array of leaf angle distribution for each specy.

Details

Leaf angle distribution measurements provided by Jan Pisek

Author(s)

W.-M. Wang (wmwangATgmail.com)

Source

Pisek, Jan, et al. "Is the spherical leaf inclination angle distribution a valid assumption for temperate and boreal broadleaf tree species?." Agricultural & Forest Meteorology 169.3(2013):186-194.

Examples

data(Pisek)
Pisek[1]

Compute the plagiophile distribution of leaf zenith angle.

Description

Compute the plagiophile distribution of leaf zenith angle.

Usage

plagiophileDis()

Value

The plagiophile distribution of leaf zenith angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

sDis<-plagiophileDis()
plot(c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5), sDis, 
xlab=expression(Leaf~zenith~angle~~(""^"o")), ylab="Leaf area freqency")

Compute the planophile distribution of leaf zenith angle.

Description

Compute the planophile distribution of leaf zenith angle.

Usage

planophileDis()

Value

The planophile distribution of leaf zenith angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

sDis<-planophileDis()
plot(c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5), sDis, 
xlab=expression(Leaf~zenith~angle~~(""^"o")), ylab="Leaf area freqency")

Plot the density of leaf area given leaf angle measurements.

Description

Plot the density of leaf area given leaf angle measurements.

Usage

plotdensity(LeafAngles, main = "Leaf angle distribution", type = "l",
  pch = 20)

Arguments

LeafAngles

The measurements of leaf angle distribution.

main

An overall title for the plot.

type

The type of plot.

pch

The symbol of plot.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

data(Pisek)
plotdensity(Pisek[[2]])

Retrieve the density of leaf area given leaf angle measurements.

Description

Retrieve the density of leaf area given leaf angle measurements.

Usage

selectClassic(LeafAngles)

Arguments

LeafAngles

The measurements of leaf angle distribution.

Value

The classic leaf angle distribution type

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

data(Falster) 
selectClassic(Falster[[2]])

Compute the spherical distribution of leaf zenith angle.

Description

Compute the spherical distribution of leaf zenith angle.

Usage

sphericalDis()

Value

The spherical distribution of leaf zenith angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

sDis<-sphericalDis()
plot(c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5), sDis, 
xlab=expression(Leaf~zenith~angle~~(""^"o")), ylab="Leaf area freqency")

Compute the symmetric distribution of leaf azimuth angle.

Description

Compute the symmetric distribution of leaf azimuth angle.

Usage

sysAziDis()

Value

The symmetric distribution of leaf azimuth angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

aDis<-sysAziDis()
plot(c(10,30,50,70,90,110,130,150,170,190,210,230,250,270,290,310,330,350), aDis, 
xlab=expression(Leaf~azimuth~angle~~(""^"o")), ylab="Leaf area freqency")

Compute the uniform distribution of leaf zenith angle.

Description

Compute the uniform distribution of leaf zenith angle.

Usage

uniformDis()

Value

The uniform distribution of leaf zenith angle.

Author(s)

Wei-Min Wang (wmwang AT gmail.com)

References

Wang, W. M., Li, Z. L., & Su, H. B. (2007). Comparison of leaf angle distribution functions: effects on extinction coefficient and fraction of sunlit foliage. Agricultural and Forest Meteorology, 143(1), 106-122.

Examples

sDis<-sphericalDis()
plot(c(4.5, 13.5, 22.5, 31.5, 40.5, 49.5, 58.5, 67.5, 76.5, 85.5), sDis, 
xlab=expression(Leaf~zenith~angle~~(""^"o")), ylab="Leaf area freqency")