| coastlineCut {oce} | R Documentation |
Cut a Coastline Object at Specified Longitude
Description
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.
Usage
coastlineCut(coastline, lon_0 = 0)
Arguments
coastline |
a coastline object. |
lon_0 |
longitude as would be given in a |
Value
a new coastline object
Caution
This function is provisional. Its behaviour, name and very existence
may change. Part of the development plan is to see if there is common
ground between this and the clipPolys function in the
PBSmapping package.
Author(s)
Dan Kelley
See Also
Other things related to coastline data:
[[,coastline-method,
[[<-,coastline-method,
as.coastline(),
coastline-class,
coastlineBest(),
coastlineWorld,
download.coastline(),
plot,coastline-method,
read.coastline.openstreetmap(),
read.coastline.shapefile(),
subset,coastline-method,
summary,coastline-method
Examples
library(oce)
data(coastlineWorld)
mapPlot(coastlineCut(coastlineWorld, lon_0 = 100),
projection = "+proj=moll +lon_0=100", col = "gray"
)