go-haversine

The Haversine formula determines the great-circle distance between two points on a sphere given their latitudes and longitudes. Important in navigation, it is a special case of a more general formula in spherical trigonometry, the law of Haversines, that relates the sides and angles of spherical triangles.

Installation

go get https://github.com/kwahome/go-haversine

Usage

Below is an example showing how to calculate the shortest path between two coordinates on the surface of the Earth.

package main

import (
	"fmt"
	"github.com/kwahome/go-haversine/pkg/haversine"
)

func main() {
	nairobi := haversine.Coordinate{
		Latitude: 1.2921,
		Longitude: 36.8219,
	}
	mombasa := haversine.Coordinate{
		Latitude: 4.0435,
		Longitude: 39.6682,
	}

	units := haversine.M
	distance := nairobi.DistanceTo(mombasa, units)
	fmt.Println("Distance from Nairobi =", nairobi, "to Mombasa =", mombasa, "in", units, "is", distance)

	units = haversine.KM
	distance = nairobi.DistanceTo(mombasa, units)
	fmt.Println("Distance from Nairobi =", nairobi, "to Mombasa =", mombasa, "in", units, "is", distance)

	units = haversine.MI
	distance = nairobi.DistanceTo(mombasa, units)
	fmt.Println("Distance from Nairobi =", nairobi, "to Mombasa =", mombasa, "in", units, "is", distance)
}

Distance from Nairobi = {latitude=1.2921, longitude=36.8219} to Mombasa = {latitude=4.0435, longitude=39.6682} in meters is 439923.26193980715
Distance from Nairobi = {latitude=1.2921, longitude=36.8219} to Mombasa = {latitude=4.0435, longitude=39.6682} in kilometers is 439.92326193980716
Distance from Nairobi = {latitude=1.2921, longitude=36.8219} to Mombasa = {latitude=4.0435, longitude=39.6682} in miles is 273.3034485571742

Development

Find the entire code in the repository:

https://github.com/kwahome/go-haversine

Use convenience scripts in ./bin to run tests and format code.

Tests:

./bin/unit_test.sh

Code formatting:

./bin/code_format.sh

Docs

https://godoc.org/github.com/kwahome/go-haversine

License

See the LICENSE file for license rights and limitations (MIT).