avec_ang: Calculate the opposites of the input radial angle(s)

In efetac/PolarMetrics: Functions for analyzing seasonal patterns in environmental variables

Description

Calculate the vertical opposite of the input radian value(s).

Usage

avec_ang(r)

Arguments

r	A numeric vector of values of radial coordinates.

Details

avec_ang returns the vertical opposite(s) of the input angles.

Value

Returns the vertical opposite of radial angle(s).

Author(s)

Bjorn J. Brooks, Danny C. Lee, William W. Hargrove, Lars Y. Pomara

References

Brooks, B.J., Lee, D.C., Desai, A.R., Pomara, L.Y., Hargrove, W.W. (2017). Quantifying seasonal patterns in disparate environmental variables using the PolarMetrics R package.

Examples

dpy <- 365                 # Days/yr
data(mndvi)                # Load data
t <- as.vector(mndvi$day)  # Days since January 1, 2000
r <- t2rad(t,dpy)          # Transform days of year to radians
v <- as.vector(mndvi$wc)   # MODIS NDVI for Willow Creek tower, WI
vx <- mean(vec.x(r,v), na.rm=TRUE) # Avg horizontal vector
vy <- mean(vec.y(r,v), na.rm=TRUE) # Avg vertical vector
vm <- vec_mag(vx,vy)       # Magnitude of average vector
rv_ang <- vec_ang(vx,vy)   # Angle of resultant vec (point of max activity)
av_ang <- avec_ang(rv_ang)  # Angle marking point of least activity

efetac/PolarMetrics documentation built on Dec. 20, 2020, 10:04 p.m.