Calculate great-circle distance between:
              Renton, WA: 0.828799, -2.132710 and,
             Redmond, OR: 0.772381, -2.114462.
  Geodesics in radians.
GCD (Spherical Law of Cosines) between Renton, WA and Redmond, OR: 368.430 km,
  (198.936 NM).
GCD (Haversine) between Renton, WA and Redmond, OR: 368.430 km,
  (198.936 NM).
GCD (Vincenty inverse formula) between Renton, WA and Redmond, OR: 368.336 km,
  (198.885 NM).