Data update

Task/Haversine-formula/NetRexx/haversine-formula.netrexx

@@ -0,0 +1,40 @@
+/*REXX pgm calculates distance between Nashville & Los Angles airports. */
+say " Nashville:  north 36°  7.2', west  86° 40.2'   =   36.12°,  -86.67°"
+say "Los Angles:  north 33° 56.4', west 118° 24.0'   =   33.94°, -118.40°"
+say
+dist=surfaceDistance(36.12,  -86.67,  33.94,  -118.4)
+say dist
+
+bef = Length(dist/1)
+kdist=format(dist/1,bef,2)
+mdist=format(dist/1.609344,bef,2)
+ndist=format(mdist*5280/6076.1,bef,2)
+say ' distance between=  '  kdist  " kilometers,"
+say '               or   '  mdist  " statute miles,"
+say '               or   '  ndist  " nautical or air miles."
+exit                                   /*stick a fork in it, we're done.*/
+/*----------------------------------SURFACEDISTANCE subroutine----------*/
+
+method radians(x) static
+  return x * Math.PI / 180
+
+method surfaceDistance(lat1,lon1,lat2,lon2) public static   /*use haversine formula for dist.*/
+  radius = 6372.8                      /*earth's mean radius in km      */
+  dLat = radians(lat2 - lat1)
+  dLon = radians(lon2 - lon1)
+  lat1 = radians(lat1)
+  lat2 = radians(lat2)
+
+  a = sin(dLat / 2)**2 + cos(lat1) * cos(lat2) * sin(dLon / 2) ** 2
+  c = 2 * asin(sqrt(a))
+
+  return radius * c
+
+method cos(x) static
+  return Rexx Math.cos(x)
+method sin(x) static
+  return Rexx Math.sin(x)
+method asin(x) static
+  return Rexx Math.asin(x)
+method sqrt(x) static
+  return Rexx Math.sqrt(x)