coastlineCut {oce} | R Documentation |
Cut a coastline file at specified longitude
coastlineCut(coastline, lon_0 = 0)
coastline |
original coastline object |
lon_0 |
longitude as would be given in a |
This can be helpful in preventing mapPlot
from producing ugly
horizontal lines in world maps. These lines occur when a coastline segment
is intersected by longitude lon_0+180. Since the coastline files in the oce
and ocedata packages are already "cut" at longitudes of -180 and 180, the present
function is not needed for default maps, which have +lon_0=0
. However,
may help with other values of lon_0
.
This function is provisional. Its behaviour, name and very existence
may change through the late months of 2015. One part of the
development plan is to see if there is common ground between this
and the clipPolys
function in the PBSmapping package.
a new coastline object
library(oce) data(coastlineWorld) ## Not run: mapPlot(coastlineCut(coastlineWorld, lon_0=100), proj="+proj=robin +lon_0=100", fill='gray') ## End(Not run)