廢話不多說,上代碼
function countDist(lat1, lng1, lat2, lng2) {//緯度1,經(jīng)度1,緯度2,經(jīng)度2
????var f = ((lat1 + lat2) / 2) * Math.PI / 180.0;
? ? var g = ((lat1 - lat2) / 2) * Math.PI / 180.0;
? ? var l = ((lng1 - lng2) / 2) * Math.PI / 180.0;
? ? var sg = Math.sin(g);
? ? var sl = Math.sin(l);
? ? var sf = Math.sin(f);
? ? var s, c, w, r, d, h1, h2;
? ? var a = 6378137.0;//地球的直徑
? ? var fl = 1 / 298.257;
? ? sg = sg * sg;
? ? sl = sl * sl;
? ? sf = sf * sf;
? ? s = sg * (1 - sl) + (1 - sf) * sl;
? ? c = (1 - sg) * (1 - sl) + sf * sl;
? ? w = Math.atan(Math.sqrt(s / c));
? ? r = Math.sqrt(s * c) / w;
? ? d = 2 * w * a;
? ? h1 = (3 * r - 1) / 2 / c;
? ? h2 = (3 * r + 1) / 2 / s;
? ? var num = d * (1 + fl * (h1 * sf * (1 - sg) - h2 * (1 - sf) * sg))
? ? return num;//返回單位:米
}
