使用scala計算兩個Gps點之間的距離
阿新 • • 發佈:2019-02-13
通常進行軌跡資料的挖掘,都會用到經緯度轉換距離。特別是Spark需要scala語言編寫,這方面的輪子比較少。
下面是該程式的列印結果object getDistance{ def main(args: Array[String]) { val lon1 = 108.956769;val lat1 = 34.229644 val lon2 = 108.958830;val lat2 =34.229701 def getDistance(lon1: Double, lat1: Double, lon2: Double, lat2: Double): Double ={ //pi為π,r為地球半徑 val pi = 3.1415926 val r: Double = 6370.99681 //a1、a2、b1、b2分別為上面資料的經緯度轉換為弧度 val a1 = lat1 * pi /180.0 val a2 = lon1 * pi /180.0 val b1 = lat2 * pi /180.0 val b2 = lon2 * pi /180.0 var t1: Double = Math.cos(a1) * Math.cos(a2) * Math.cos(b1)* Math.cos(b2) var t2: Double = Math.cos(a1) * Math.sin(a2) * Math.cos(b1)* Math.sin(b2) var t3: Double = Math.sin(a1) * Math.sin(b1) val distance = Math.acos(t1 + t2 + t3) * r distance } println(getDistance(lon1,lat1,lon2,lat2)) } }