computeG: Compute the mean projection of unit leaf area on the plane...

Description Usage Arguments Value Author(s) References Examples

View source: R/computeG.R

Description

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

Usage

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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

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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))
}

RLeafAngle documentation built on June 20, 2017, 9:10 a.m.