我做错了什么?我试图计算距离gpx(lat,lon)文件的距离,但收到了错误的结果。
function distance($lat1, $lon1, $lat2, $lon2) {
$theta = $lon1 - $lon2;
$dist = sin(deg2rad($lat1)) * sin(deg2rad($lat2)) + cos(deg2rad($lat1)) * cos(deg2rad($lat2)) * cos(deg2rad($theta));
$dist = acos($dist);
$dist = rad2deg($dist);
$kilometers = $dist * 60 * 1.1515 ;
return $kilometers;
}
$gpx_file_source = simplexml_load_file($gpx_patch);
$j=0;
foreach($gpx_file_source->trk->trkseg->trkpt as $point){
if($j%2==0){
$lat1=$point->attributes()[0];
$lon1=$point->attributes()[1];
}else{
$lat2=$point->attributes()[0];
$lon2=$point->attributes()[1];
$totaldistance=distance(''.$lat1.'', ''.$lon1.'', ''.$lat2.'', ''.$lon2.'').;
$totaldistance+=$totaldistance;
}
$j++;
}
echo $totaldistance; //0.00011797444243905
我的结果是: 0.00011797444243905 km
正确的结果: 17.35 km
GPX文件: http://itros.us/distance.gpx
答案 0 :(得分:0)
我改变了计数功能并且正在工作!
3958*3.1415926*sqrt(($lat2-$lat1)*($lat2-$lat1) + cos($lat2/57.29578)*cos($lat1/57.29578)*($lon2-$lon1)*($lon2-$lon1))/180