Gets the relative heading between two track segments (three localizations)
using the law of cosines.
The turning angle is returned in degrees.
Users should apply this function to one individual at a time, ideally by
splittng a dataframe with multiple individuals into a list of dataframes.
Usage
atl_turning_angle(data, x = "x", y = "y", time = "time")
Arguments
- data
A dataframe or similar which must have the columns
specified by x, y, and time.
- x
The x coordinate.
- y
The y coordinate.
- time
The timestamp in seconds since the UNIX epoch.
Value
A vector of turning angles in degrees.
Negative degrees indicate 'left' turns. There are two fewer
angles than the number of rows in the dataframe.
Author
Pratik R. Gupte & Allert Bijleveld
Examples
if (FALSE) { # \dontrun{
data$angle <- atl_turning_angle(data,
x = "x", y = "y", time = "time"
)
} # }
