ang_speed {swaRm}

Angular Speeds

Description

Given a set of locations defining a trajectory, this function approximates their instantaneous instantaneous angular speeds computed as the difference between successive headings divided by the time between these successive headings.

Usage

ang_speed(x, y, t, geo = FALSE)

angSpeed(x, y, t, geo = FALSE)

Arguments

x

A vector of x (or longitude) coordinates corresponding to a single trajectory.

y

A vector of y (or latitude) coordinates corresponding to a single trajectory.

t

A vector of timestamps corresponding to a single trajectory.

geo

A logical value indicating whether the locations are defined by geographic coordinates (pairs of longitude/latitude values). Default: FALSE.

Value

A vector of the same length as x, y and t corresponding to the approximated instantaneous angular speeds along the trajectory.

Author(s)

Simon Garnier, [e-mail]

See Also

heading, ang_acc

Examples

x <- rnorm(25)
y <- rnorm(25, sd = 3)
t <- as.POSIXct(1:25, origin = Sys.time())
ang_speed(x, y, t)