Each pair in the longitude
and latitude
vectors is considered
in turn. For long vectors, this may be slow.
geodGc(longitude, latitude, dmax)
vector of longitudes, in degrees east
vector of latitudes, in degrees north
maximum angular separation to tolerate between sub-segments, in degrees.
Data frame of longitude
and latitude
.
http://williams.best.vwh.net/avform.htm#Intermediate
(link worked for years but failed 2017-01-16).
Other functions relating to geodesy:
geodDist()
,
geodXy()
,
geodXyInverse()
# \donttest{
library(oce)
data(coastlineWorld)
mapPlot(coastlineWorld,
type = "l",
longitudelim = c(-80, 10), latitudelim = c(35, 80),
projection = "+proj=merc"
)
# Great circle from New York to Paris (Lindberg's flight)
l <- geodGc(c(-73.94, 2.35), c(40.67, 48.86), 1)
mapLines(l$longitude, l$latitude, col = "red", lwd = 2)
# }