toptailgs: Clip the first and last n metres of SpatialLines
Description
Takes lines and removes the start and end point, to a distance determined
by the user. Uses the geosphere::distHaversine function and requires
coordinates in WGS84 (lng/lat).
Usage
toptailgs(l, toptail_dist, tail_dist = NULL)
Arguments
l
A SpatialLines object
toptail_dist
The distance (in metres) to top the line by.
Can be either a single value or a vector of the same length as the
SpatialLines object. If tail_dist is missing, is used as the tail distance.
tail_dist
The distance (in metres) to tail the line by. Can be
either a single value or a vector of the same length as the SpatialLines
object.