yats.git

diff --git a/server/geo/distances.go b/server/geo/distances.go
new file mode 100644
index 0000000000000000000000000000000000000000..94f7a0e323f9a42e48f947288d9e6f9e7c9c7dcf
--- /dev/null
+++ b/server/geo/distances.go
@@ -0,0 +1,41 @@
+package geo
+
+import "math"
+
+type coordinate struct {
+	lat float64
+	lon float64
+}
+
+// haversin(θ) function
+func hsin(theta float64) float64 {
+	return math.Pow(math.Sin(theta/2), 2)
+}
+
+// Distance function returns the distance (in meters) between two points of
+//
+//	a given longitude and latitude relatively accurately (using a spherical
+//	approximation of the Earth) through the Haversin Distance Formula for
+//	great arc distance on a sphere with accuracy for small distances
+//
+// point coordinates are supplied in degrees and converted into rad. in the func
+//
+// distance returned is meters
+// http://en.wikipedia.org/wiki/Haversine_formula
+func Distance(coordinate1, coordinate2 coordinate) float64 {
+	// convert to radians
+	// must cast radius as float to multiply later
+
+	var la1, lo1, la2, lo2, r float64
+	la1 = coordinate1.lat * math.Pi / 180
+	lo1 = coordinate1.lon * math.Pi / 180
+	la2 = coordinate2.lat * math.Pi / 180
+	lo2 = coordinate2.lon * math.Pi / 180
+
+	r = 6378100 // Earth radius in meters
+
+	// calculate
+	h := hsin(la2-la1) + math.Cos(la1)*math.Cos(la2)*hsin(lo2-lo1)
+
+	return 2 * r * math.Asin(math.Sqrt(h))
+}




diff --git a/server/geo/distances_test.go b/server/geo/distances_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..6c6b983bf8a4d1673fdd3e5b00a21ae5531f9e90
--- /dev/null
+++ b/server/geo/distances_test.go
@@ -0,0 +1,26 @@
+package geo
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestDistance(t *testing.T) {
+
+	winnipeg := coordinate{49.895077, -97.138451}
+	regina := coordinate{50.445210, -104.618896}
+
+	result := Distance(winnipeg, regina)
+
+	fmt.Printf("%f\n", result)
+}
+
+func TestGenerateAllNodes(t *testing.T) {
+	for lon := -180; lon <= 180; lon += 10 {
+		for lat := -90; lat <= 90; lat += 10 {
+			fmt.Printf("Lon: %d Lat: %d\n", lon, lat)
+		}
+		fmt.Printf("\n")
+		//	lon += 10
+	}
+}