| geopath {plotKML} | R Documentation |
Derives a SpatialLines class object showing the shortest path between the two geographic locations and based on the Haversine Formula for Great Circle distance.
geopath(lon1, lon2, lat1, lat2, ID, n.points, print.geo = FALSE)
lon1 |
longitude coordinate of the first point |
lon2 |
longitude coordinate of the second point |
lat1 |
latitude coordinate of the first point |
lat2 |
latitude coordinate of the second point |
ID |
(optional) point ID character |
n.points |
number of intermediate points |
print.geo |
prints the distance and bearing |
Number of points between the start and end point is derived using a simple formula:
round(sqrt(distc)/sqrt(2), 0)
where distc is the Great Circle Distance.
Bearing is expressed in degrees from north. Distance is expressed in kilometers (Great Circle Distance).
Tomislav Hengl
fossil package (https://CRAN.R-project.org/package=fossil)
Haversine formula from Math Forums (http://mathforum.org/dr.math/)
kml_layer.SpatialLines, kml_layer.STTDF, fossil::earth.bear
library(fossil) ams.ny <- geopath(lon1=4.892222, lon2=-74.005973, lat1=52.373056, lat2=40.714353, print.geo=TRUE) # write to a file: kml(ams.ny)