move (version 4.2.5)

timeLag: Time lags between the locations of a movement track

Description

Calculates the time lags between consecutive locations of a track.

Usage

# S4 method for .MoveTrackSingle
timeLag(x,...)
  # S4 method for .MoveTrackStack
timeLag(x,units, ...)

Value

Time lags in the specified units.

If a move or moveBurst object is provided, a numeric vector one element shorter than the number of locations is obtained.

If a moveStack object is provided, a list with one element per individual containing a numeric vector one element shorter than the number of locations is obtained.

Arguments

x

a move, moveStack or moveBurst object

units

The units used for the conversion (e.g. "secs", "mins", "hours", "days" or "weeks"). They should be specified for a moveStack to ensure the same units between individuals. Optional (but recommended).

...

Currently not implemented.

Author

Bart Kranstauber & Anne Scharf

Details

Optionally the argument units can be passed on to ensure the time lag is in a certain unit, this is especially useful in case of a moveStack. For more information on the units argument see the help of difftime.

Examples

## time lags from a Move object 
data(leroy)
head(timeLag(leroy, units="hours"))
# to add this information to the move object, a "NA" has to be assigened
# e.g. to the first location (it also could be assigend to the first location).
leroy$timeLag <- c(timeLag(leroy, units="hours"), NA)

## time lags from a MoveStack object
data(fishers)
str(timeLag(fishers, units="mins"))
# to add this information to the moveStack object, a "NA" has to be assigened
# e.g. to the duration is assigned to the first location of each segment
fishers$timeLag <- unlist(lapply(timeLag(fishers, units="mins"),  c, NA))