first commit

.gitignore

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+node_modules
+.DS_Store
+npm-debug.log

.npmignore

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+node_modules
+.DS_Store
+npm-debug.log

README.md

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+# Haversine
+A simple haversine formula module for Node.js
+
+I created this small module for an application I created and figured I would package it up to share.
+
+## Installation
+`$ npm install haversine`
+
+## Usage
+### haversine(start, end, options)
+
+    var haversine = require('haversine')
+
+    start = {
+      latitude: 10,
+      longitude: 11,
+    }
+    end = {
+      latitude: 11,
+      longitude: 10
+    }
+
+    console.log(haversine(start, stop))
+    console.log(haversine(start, stop, {unit: 'km'}))
+
+## Future
+I plan on adding more options soon including a threshold check.

haversine.js

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+// haversine
+// By Nick Justice (niix)
+// https://github.com/niix/haversine
+
+var haversine = (function() {
+
+  // convert to radians
+  var toRad = function(num) {
+    return num * Math.PI / 180
+  }
+
+  return function haversine(start, end, options) {
+    var miles = 3960
+    var km    = 6371
+    options   = options || {}
+
+    R = options.unit === 'km' ? km : miles
+
+    var dLat = toRad(end.latitude - start.latitude)
+    var dLon = toRad(end.longitude - start.longitude)
+    var lat1 = toRad(start.latitude)
+    var lat2 = toRad(end.latitude)
+
+    var a = Math.sin(dLat/2) * Math.sin(dLat/2) +
+            Math.sin(dLon/2) * Math.sin(dLon/2) * Math.cos(lat1) * Math.cos(lat2)
+    var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a))
+
+    return R * c
+  }
+
+})()
+
+module.exports = haversine

package.json

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+{
+  "name": "haversine",
+  "version": "0.0.1",
+  "description": "A simple haversine module",
+  "main": "haversine.js",
+  "directories": {
+    "test": "test"
+  },
+  "scripts": {
+    "test": "./test/test.js"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/niix/haversine"
+  },
+  "keywords": [
+    "haversine",
+    "distance",
+    "coordinates",
+    "geolocation"
+  ],
+  "author": "Nick Justice (niix)",
+  "license": "MIT"
+}

test/test.js

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+var haversine = require('../haversine');
+
+start = {
+  latitude: 50.03,
+  longitude: 05
+}
+
+end = {
+  latitude: 58.38,
+  longitude: 03
+}
+
+// inserting values directly
+console.log(haversine({latitude: 12, longitude: 11}, {latitude: 10, longitude: 10}))
+
+// using objects
+console.log(haversine(start, end))
+
+// using objects with unit conversion
+console.log(haversine(start, end, {unit: 'km'}))