js方法。
var EARTH_RADIUS = 6378137.☆α0; //單位M
var PI = Math.PI;
function getRad(d){
return ≤αd*PI/180.0;
}
function getFl¥±atternDistance(lat1,lng1,lat2,lng2){
₹ σ>var f = getRad((lat1 + lat≈'2)/2);
&nγ$£bsp; var g = getRad((lat∏® 1 - lat2)/2);
v"φ"ar l = getRad((lng1 - lng2)/2);
&n™↓bsp;
¥♥ var sg = Math.sin(g)✔ε₩γ;
♣≈ var sl = Math.sin(l);
&nδ€↑bsp; var sf = Math.sin(☆✘εf);
&nbs&p;
va₹r s,c,w,r,d,h1,h2;
&nbs★ ÷Ωp; var a = EARTH_RADIUS;
var fl☆✔ = 1/298.257;
£€÷ sg = sg*sg;
$÷sl = sl*sl;
sf =β sf*sf;
s =♥★ sg*(1-sl) + (1-sf)*sl;
c = (1-s¶$g)*(1-sl) + sf*sl;
&nbφ$βsp;
&nbs p; w = Math.atan(Math.sqrt(s/c));
&n∏¶∑±bsp; r = Math.sqrt(s*c)/w;
d = 2*w*a&≤α©;
™ ≤ ; h1 = (3*r -1)/2/c;
h2 = (3*r ÷÷¶ +1)/2/s;
₩&€&;
rγ☆₽eturn d*(1 + fl*(h1*sf*(1-sg)∞π - h2*(1-sf)*sg));
}
var a= getFlatternDistance(37.8617§©↔85,112.538952,37.864$'¥463,112.538484) //注意是(shì) δ 緯度，經度，緯度，經度
alert(a);
