如何在php中计算两个位置之间的距离（以公里为单位）？

Question

我有一个存储服务的表，服务表的列是纬度，经度，即服务的位置。

现在我想获取用户的当前位置并搜索距离用户10公里左右的可用服务。

为此，我搜索了如何计算两个位置之间的距离并尝试了其中一个代码，但它在 JSON 中给出了一些语法错误。

错误是语法错误，（意外的'S'），我也没有通过这个公式得到以公里为单位的结果。

     public function searchVendors($lattitudeFrom,$longitudeFrom)
    {
        $lattitudeTo = -10.4212157;
        $longitudeTo = 28.6031842;


        $dist = $this -> haversineGreatCircleDistance($latitudeFrom, $longitudeFrom, $latitudeTo, $longitudeTo, $earthRadius = 6371000);

        return $dist;

    }

 public function haversineGreatCircleDistance($latitudeFrom, $longitudeFrom, $latitudeTo, $longitudeTo, $earthRadius = 6371000)
{
    // convert from degrees to radians
    $latFrom = deg2rad($latitudeFrom);
    $lonFrom = deg2rad($longitudeFrom);
    $latTo = deg2rad($latitudeTo);
    $lonTo = deg2rad($longitudeTo);

    $latDelta = $latTo - $latFrom;
    $lonDelta = $lonTo - $lonFrom;

    $angle = 2 * asin(sqrt(pow(sin($latDelta / 2), 2) +
        cos($latFrom) * cos($latTo) * pow(sin($lonDelta / 2), 2)));
    return $angle * $earthRadius;
}

getVendors.php

  <?php

header("Content-type: application/json");

   // if ( $_SERVER['REQUEST_METHOD']=='POST') {
        include_once ("../include/Vendor.php");
    try {

    $con = DB::getConnection();

    $raw = file_get_contents("php://input");
    $data = json_decode($raw, true);

    $longitude = $data->longitude;
    $lattitude = $data->lattitude;

    $v = new Vendor();
    $response = $v -> searchVendors($lattitude,$longitude);


    json_encode($response);


    echo $response;

        if ( $response == null ) {
            $response = json_encode(array("result" => -2, "message" => "Empty result"));
            echo $response;
        } else {
            echo $response;
        }
    } catch(Exception $e) {
        $result = array("result" => -1, "message" => $e -> getMessage());
        echo json_encode($result);
        }
//}
?>

我怎样才能做到这一点？任何人都可以帮忙.. php 中非常新。

Answer 1

php cal_dist(a,b,key=none,spec=km)

Answer 2

尝试使用此代码以 KM 或 MILES 为单位查找距离

function distance($lat1, $lon1, $lat2, $lon2, $unit) {

      $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);
      $miles = $dist * 60 * 1.1515;
      $unit = strtoupper($unit);

      if ($unit == "K") {
        return ($miles * 1.609344);
      } else if ($unit == "N") {
          return ($miles * 0.8684);
        } else {
            return $miles;
          }
    }