<?php
//獲取該點周圍的4個點
$distance = 1;//範圍(單位千米)
$lat = 113.873643;
$lng = 22.573969;
define('EARTH_RADIUS', 6371);//地球半徑,平均半徑爲6371km
$dlng = 2 * asin(sin($distance / (2 * EARTH_RADIUS)) / cos(deg2rad($lat)));
$dlng = rad2deg($dlng);
$dlat = $distance/EARTH_RADIUS;
$dlat = rad2deg($dlat);
$squares = array('left-top'=>array('lat'=>$lat + $dlat,'lng'=>$lng-$dlng),
'right-top'=>array('lat'=>$lat + $dlat, 'lng'=>$lng + $dlng),
'left-bottom'=>array('lat'=>$lat - $dlat, 'lng'=>$lng - $dlng),
'right-bottom'=>array('lat'=>$lat - $dlat, 'lng'=>$lng + $dlng)
);
print_r($squares['left-top']['lat']);
//從數庫查詢匹配的記錄
$info_sql = "select * from `A` where lat<>0 and lat>{$squares['right-bottom']['lat']} and lat<{$squares['left-top']['lat']} and lng>{$squares['left-top']['lng']} and lng<{$squares['right-bottom']['lng']} ";
//獲取兩點之間的距離
function getDistanceBetweenPointsNew($latitude1, $longitude1, $latitude2, $longitude2) {
$theta = $longitude1 - $longitude2;
$miles = (sin(deg2rad($latitude1)) * sin(deg2rad($latitude2))) + (cos(deg2rad($latitude1)) * cos(deg2rad($latitude2)) * cos(deg2rad($theta)));
$miles = acos($miles);
$miles = rad2deg($miles);
$miles = $miles * 60 * 1.1515;
$feet = $miles * 5280;
$yards = $feet / 3;
$kilometers = $miles * 1.609344;
$meters = $kilometers * 1000;
return compact('miles','feet','yards','kilometers','meters');
}
$point1 = array('lat' => 40.770623, 'long' => -73.964367);
$point2 = array('lat' => 40.758224, 'long' => -73.917404);
$distance = getDistanceBetweenPointsNew($point1['lat'], $point1['long'], $point2['lat'], $point2['long']);
foreach ($distance as $unit => $value) {
echo $unit.': '.number_format($value,4).'<br />';
}
?>
個人思路:
查詢某個點附近的東西,例如查詢當前位置周圍5千米的酒店,
遍歷數據庫所有的酒店,取出經度緯度,放入二維數組。分別帶入getDistanceBetweenPointNew(),取出一個值,即距離米,查詢的時候距離小於5千米的都查詢出來。
SELECT
*,(
6371 * acos(
cos(radians(緯度)) * cos(radians(lat)) * cos(
radians(lng) - radians(經度)
) + sin(radians(緯度)) * sin(radians(lat))
)
) AS distance
FROM
acc_sys_t_city2
having distance <5
ORDER BY
distance
LIMIT 0,
50;
其中,radians()是mysql的函數,可以換成deg2rad(),這個是php 的函數,意思是角度轉成弧度。
這裏還推薦另外一個鏈接介紹https://blog.csdn.net/zhc2006/article/details/49688091