# File lib/geo_ruby/simple_features/point.rb, line 44 def spherical_distance(point,radius=6370997.0) deg_to_rad = 0.0174532925199433 radlat_from = lat * deg_to_rad radlat_to = point.lat * deg_to_rad dlat = (point.lat - lat) * deg_to_rad dlon = (point.lon - lon) * deg_to_rad a = Math.sin(dlat/2)**2 + Math.cos(radlat_from) * Math.cos(radlat_to) * Math.sin(dlon/2)**2 c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a)) radius * c end