计算百度地图2点间的距离

原文：http://blog.csdn.net/pleasurelong/article/details/26855049

我修改了一下：

var pk = 180 / 3.14169;  var a1 = 39.92925 / pk; // jwd:116.397928,39.92925;pmzb:12957499.06,4827983.94;level:16var a2 = 116.397928 / pk;  var b1 = 39.92925 / pk;  // jwd:116.408456,39.929637;pmzb:12958671.05,4828039.9;level:16var b2 = 116.408456 / pk;  var t1 = Math.cos(a1) * Math.cos(a2) * Math.cos(b1) * Math.cos(b2);  var t2 = Math.cos(a1) * Math.sin(a2) * Math.cos(b1) * Math.sin(b2);  var t3 = Math.sin(a1) * Math.sin(b1);  var tt = Math.acos(t1 + t2 + t3);  alert(6366000 * tt);

    上面是故宫东北角和西北角的经纬度。