GCdistance: Great circle distance

In insol: Solar Radiation

Description

Great circle or geodesic distance.

Usage

GCdistance(lat1,lon1,lat2,lon2)

Arguments

lat1	Latitude of points of origin.
lon1	Longitude of points of origin.
lat2	Latitude of points of destination.
lon2	Longitude of points of destination.

Value

Distance between origin and destination points in metres.

Author(s)

Javier G. Corripio

References

https://edwilliams.org/avform.htm,

http://mathworld.wolfram.com/GreatCircle.html.

Examples

GCdistance(0,0,0,180)*2

# distance between the center of US states 
data(state)
ddd = matrix(nrow=50,ncol=50,dimnames=list(state.name,state.name))
for (i in 1:50){
	for (j in 1:50){
		distij = GCdistance(state.center$y[i],state.center$x[i],
			state.center$y[j],state.center$x[j])
		# round to miles
		ddd[i,j]=round(distij/1609.344,2)
	}
}
# format and print results for the 10 firsts states
as.dist(ddd[1:10,1:10])

insol documentation built on Feb. 10, 2021, 5:08 p.m.