• js计算地球两个经纬度之间的距离


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    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title></title>
         <script type="text/javascript" src="http://apps.bdimg.com/libs/jquery/1.6.4/jquery.js"></script>
        <script type="text/javascript">
            var EARTH_RADIUS = 6378137.0;    //单位M
            var PI = Math.PI;
    
            function getRad(d) {
                return d * PI / 180.0;
            }
    
            /**
            * caculate the great circle distance
            * @param {Object} lat1(纬度1)
            * @param {Object} lng1(经度1)
            * @param {Object} lat2(纬度2)
            * @param {Object} lng2(经度2)
            */
            //第一种方法:这种算法是把地球当作规则的球面来计算的咯,这种方法不是很精准咯,这个还要取决你定位的精准度咯
            function getGreatCircleDistance(lat1, lng1, lat2, lng2) {
                var radLat1 = getRad(lat1);
                var radLat2 = getRad(lat2);
    
                var a = radLat1 - radLat2;
                var b = getRad(lng1) - getRad(lng2);
    
                var s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));
                s = s * EARTH_RADIUS;
                s = Math.round(s * 10000) / 10000.0;
    
                alert(s);
            }
            //第一种方法:地球是椭圆的,所以会有这种算法
            function getFlatternDistance(lat1, lng1, lat2, lng2) {
                var f = getRad((lat1 + lat2) / 2);
                var g = getRad((lat1 - lat2) / 2);
                var l = getRad((lng1 - lng2) / 2);
    
                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 = EARTH_RADIUS;
                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;
                alert( d * (1 + fl * (h1 * sf * (1 - sg) - h2 * (1 - sf) * sg)));
            }
            $(function () {
                getFlatternDistance(28.89596, 105.443985, 28.896462, 105.444291);
            });
        </script>
    </head>
    <body>
    63.3422
    </body>
    </html>
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  • 原文地址:https://www.cnblogs.com/LoveQin/p/5424265.html
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