The use of offset is a convenient way to define reference dates in an
object of class ltraj. For example, if the animal is monitored
every night, from 18H00 to 06H00, the fact that the beginning and the
end of the monitoring do not correspond to the same day may cause
difficulties to handle the trajectory. Though these difficulties are
not unsurmountable, it is often convenient to deduct an offset to the
trajectory, so that the first relocation is collected at 0H and the
last one at 12H00 the same day (i.e., in this example, an offset of
18 hours).
See Also
ltraj for additional information on objects of
class ltraj