根据经纬度判断直线距离

/**
* 根据门店距离排序
* @param $data
* @param string $longitude 经度
* @param string $latitude 纬度
* @return array
*/
public function sortByDistance($longitude,$latitude)
{
// 根据距离排序
$list =Db::table('benben_store_shop')
->where('status',1)
->where('is_delete',0)
->order('id desc')
->select();

    $sortArr = [];
    foreach ($list as &$shop) {
        // 计算距离
        $distance = self::getDistance((float)$longitude, (float)$latitude, (float)$shop['longitude'], (float)$shop['latitude']);

        // 排序列
        $sortArr[] = $distance;
        $shop['distance'] = $distance;
        if ($distance >= 1000) {
            $distance = bcdiv((string)$distance, (string)1000, 2);
            $shop['distance_unit'] = $distance . 'km';
        } else
            $shop['distance_unit'] = $distance . 'm';
    }
    // 根据距离排序
    array_multisort($sortArr, SORT_ASC, $list);
    return json($list);;
}

/**
 * 获取两个坐标点的距离
 * @param float $ulon
 * @param float $ulat
 * @param float $slon
 * @param float $slat
 * @return float
 */
private static function getDistance(float $ulon, float $ulat, float $slon, float $slat)
{
    // 地球半径
    $R = 6378137;
    // 将角度转为弧度
    $radLat1 = deg2rad($ulat);
    $radLat2 = deg2rad($slat);
    $radLng1 = deg2rad($ulon);
    $radLng2 = deg2rad($slon);
    // 结果
    $s = acos(cos($radLat1) * cos($radLat2) * cos($radLng1 - $radLng2) + sin($radLat1) * sin($radLat2)) * $R;
    // 精度
    $s = round($s * 10000) / 10000;
    return round($s);
}