zoukankan      html  css  js  c++  java
  • PHP查询附近的人及其距离的实现方法

    1、附近的人

    //获取该点周围的4个点
    $distance = 1;//范围(单位千米)
    $lat = 113.873643;
    $lng = 22.573969;
    define('EARTH_RADIUS', 6371);//地球半径,平均半径为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']);
    //从数库查询匹配的记录
    $info_sql = "select * from `A` where lat<>0 and lat>{$squares['right-bottom']['lat']} and lat<{$squares['left-top']['lat']} and lng>{$squares['left-top']['lng']} and lng<{$squares['right-bottom']['lng']} ";

    2、两点之间的距离

    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 />';
    }

    转“https://www.php.cn/php-weizijiaocheng-316.html”

  • 相关阅读:
    观察者模式
    盛最多水的容器
    单例模式
    (七)STL适配器
    (六)STL仿函数functor
    (五)STL算法
    吴恩达《机器学习》课程总结(3)_线性代数回顾
    吴恩达《机器学习》课程总结(2)_单变量线性回归
    吴恩达《机器学习》课程总结(1)_绪论:初识机器学习
    图像表示与描述
  • 原文地址:https://www.cnblogs.com/zxf100/p/11813396.html
Copyright © 2011-2022 走看看