vec_mag: Calculate Euclidean magnitudes from horizontal and vertical...

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

Description

Calculate the magnitude (Euclidean distance) for each pair of horizontal and vertical component vectors.

Usage

vec_mag(vx, vy)

Arguments

vx	A numeric vector of 1 or more values representing horizontal components of Euclidean vectors. vx can be obtained using vec.x.
vy	A numeric vector of 1 or more values representing vertical components of Euclidean vectors. vy can be obtained using vec.y.

Details

vec_mag returns the Euclidean distance of each pair of horizontal and vertical component vectors according to:

√{vx^2 + vy^2}

Value

Returns the Euclidean distance corresponding to each horizontal and vertical component vector pair.

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 (length) of average vector

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