getgreatarc {GEOmap}R Documentation

Great Circle Arc

Description

Get points along great circle between two locations

Usage

getgreatarc(lat1, lon1, lat2, lon2, num)

Arguments

lat1 Latitude, point 1 (degrees)
lon1 Longitude, point 1 (degrees)
lat2 Latitude, point 2 (degrees)
lon2 Longitude, point 2 (degrees)
num number of points along arc

Value

lat Latitude
lon Longitude

Author(s)

Jonathan M. Lees<jonathan.lees@unc.edu>

Examples

PARIS = c(48.8666666666667, 2.33333333333333)
RIODEJANEIRO =c( -22.9,  -43.2333333333333)

g = getgreatarc(PARIS[1],PARIS[2], RIODEJANEIRO[1], RIODEJANEIRO[2],
100)

data(worldmap)

plotGEOmap(worldmap, add=FALSE, shiftlon=180)

lines(g$lon+180, g$lat)


[Package GEOmap version 1.4-0 Index]