gcdist {ncf} | R Documentation |
Greater circle distance function to calculate spatial distance from lat-long data. Called by various functions.
gcdist(x1, y1, x2, y2)
x1 |
longitude 1. |
x2 |
longitude 2. |
y1 |
latitude 1. |
y2 |
latitude 2. |
Function for great circle distance – due to T. Keitt. See http://www.census.gov/cgi-bin/geo/gisfaq?Q5.1.
The distance in km is returned
Tim H. Keitt