5

Google Maps Reverse-Geocoding API から緯度と経度を取得した後、次のようなものが必要です。

mysql_query("SELECT users.*, ".mysql_distance_column($lat,$lng)." FROM users ORDER BY DISTANCE";

function mysql_distance_column($lat=40 , $lng=-73) {

   $defaultLatitudeColumn = 'user_lat'; 
   $defaultLongitudeColumn='user_lng';
   $defaultColumnName='user_distance';
    return  "(( 
(3956 * 2 * ASIN(SQRT( POWER(SIN(({$lat} - abs({$defaultLatitudeColumn})) 
* pi()/180 / 2), 2) + COS({$lat} * pi()/180 ) 
* COS(abs({$defaultLatitudeColumn}) * pi()/180) 
* POWER(SIN(({$lng} - {$defaultLongitudeColumn}) * pi()/180 / 2), 2) ))
 )) ) as {$defaultColumnName} ";

}

更新 これを機能させることができません

delimiter //
CREATE FUNCTION `GeoDistMiles`( lat1 FLOAT (10,6), lon1 FLOAT (10,6), lat2 FLOAT (10,6), lon2 FLOAT (10,6) ) 
RETURNS FLOAT 
DETERMINISTIC 
NO SQL
BEGIN
  DECLARE pi, q1, q2, q3 FLOAT (10,6);
  DECLARE rads FLOAT (10,6) DEFAULT 0;
  SET pi = PI();
  SET lat1 = lat1 * pi / 180;
  SET lon1 = lon1 * pi / 180;
  SET lat2 = lat2 * pi / 180;
  SET lon2 = lon2 * pi / 180;
  SET q1 = COS(lon1-lon2);
  SET q2 = COS(lat1-lat2);
  SET q3 = COS(lat1+lat2);
  SET rads = ACOS( 0.5*((1.0+q1)*q2 - (1.0-q1)*q3) );
  RETURN 3963.346 * rads;
END
4

5 に答える 5

3

これが私が使用する式です。地球は完全な球体ではないため、結果が完全になることはありません。

CREATE DEFINER=`root`@`localhost` FUNCTION `GeoDistMiles`( lat1 FLOAT, lon1 FLOAT, lat2 FLOAT, lon2 FLOAT ) RETURNS float
始める
  DECLARE pi, q1, q2, q3 FLOAT;
  DECLARE rads FLOAT DEFAULT 0;
  SET pi = PI();
  SET lat1 = lat1 * pi / 180;
  SET lon1 = lon1 * pi / 180;
  SET lat2 = lat2 * pi / 180;
  SET lon2 = lon2 * pi / 180;
  SET q1 = COS(lon1-lon2);
  SET q2 = COS(lat1-lat2);
  SET q3 = COS(lat1+lat2);
  SET rads = ACOS( 0.5*((1.0+q1)*q2 - (1.0-q1)*q3) );
  RETURN 3963.346 * ラド;
終わり
于 2011-02-02T18:46:08.263 に答える
1

こんにちは、仕事に使える簡単な手順があります。

手順は非常に簡単で、2 つの都市間の距離を計算します。自分のやり方で変更できます。

drop procedure if exists select_lattitude_longitude;


delimiter //

create procedure select_lattitude_longitude(In CityName1 varchar(20) , In CityName2 varchar(20))

begin

declare origin_lat float(10,2);

declare origin_long float(10,2);

declare dest_lat float(10,2);

declare dest_long float(10,2);

if CityName1  Not In (select Name from City_lat_lon) OR CityName2  Not In (select Name from City_lat_lon) then

select 'The Name Not Exist or Not Valid Please Check the Names given by you' as Message;


else

select lattitude into  origin_lat from City_lat_lon where Name=CityName1;

select longitude into  origin_long  from City_lat_lon where Name=CityName1;

select lattitude into  dest_lat from City_lat_lon where Name=CityName2;

select longitude into  dest_long  from City_lat_lon where Name=CityName2;


select  origin_lat as CityName1_lattitude,
origin_long as CityName1_longitude,
dest_lat as CityName2_lattitude,
dest_long as CityName2_longitude;


SELECT 3956 * 2 * ASIN(SQRT( POWER(SIN((origin_lat - dest_lat) * pi()/180 / 2), 2) + COS(origin_lat * pi()/180) * COS(dest_lat * pi()/180) * POWER(SIN((origin_long-dest_long) * pi()/180 / 2), 2) )) * 1.609344 as Distance_In_Kms ;


end if;

end ;

//

delimiter ;
于 2011-10-03T11:05:58.537 に答える
1

http://en.wikipedia.org/wiki/Haversine_formulaを使用しようとしていると思います。

これは軽くテストされていますが、式は次のようになるはずです。

(ROUND((3956 * 2 * ASIN(SQRT(POWER(SIN(({$lat} - {$defaultLatitudeColumn}) * pi() / 180 / 2), 2) + COS({$lat} * pi()/180 ) * COS({$defaultLatitudeColumn} * pi()/180) *POWER(SIN(({$lng} - {$defaultLongitudeColumn}) * pi()/180 / 2), 2) )) )*{$magicNumber}) )/{$magicNumber}

（腹筋の呼び出しを削除しました。）

于 2011-02-02T18:58:00.367 に答える
0 
SELECT ACOS(COS(RADIANS(lat)) *
COS(RADIANS(lon)) * COS(RADIANS(34.7405350)) * COS(RADIANS(-92.3245120)) +
COS(RADIANS(lat)) * SIN(RADIANS(lon)) * COS(RADIANS(34.7405350)) * 
SIN(RADIANS(-92.3245120)) + SIN(RADIANS(lat)) * SIN(RADIANS(34.7405350))) * 
3963.1 AS Distance
FROM Stores 
WHERE 1
HAVING Distance <= 50

PHPでの使用方法は次のとおりです。

// Find rows in Stores within 50 miles of $lat,$lon
$lat = '34.7405350';
$lon = '-92.3245120';

$sql = "SELECT Stores.*, ACOS(COS(RADIANS(lat)) *
COS(RADIANS(lon)) * COS(RADIANS($lat)) * COS(RADIANS($lon)) +
COS(RADIANS(lat)) * SIN(RADIANS(lon)) * COS(RADIANS($lat)) * 
SIN(RADIANS($lon)) + SIN(RADIANS(lat)) * SIN(RADIANS($lat))) * 
3963.1 AS Distance
FROM Stores 
WHERE 1
HAVING Distance <= 50";
于 2011-09-17T15:57:48.860 に答える