php数据有关问题，

php数据问题，请教高手！
有这样一个数组：

Array

(

    [0] => Array

        (

            [time] => 1382060855000

            [day] => 2013-10-18

            [latitude] => 39.9289

            [longitude] => 116.3883

        )



    [1] => Array

        (

            [time] => 1382060855000

            [day] => 2013-10-18

            [latitude] => 42

            [longitude] => 43.5

        )



    [2] => Array

        (

            [time] => 1382060855000

            [day] => 2013-10-18

            [latitude] => 38.9122

            [longitude] => 121.6022

        )



    [3] => Array

        (

            [time] => 1382060855000

            [day] => 2013-10-18

            [latitude] => 40.5525

            [longitude] => -74.2915

        )



    [4] => Array

        (

            [time] => 1382060855000

            [day] => 2013-10-18

            [latitude] => 40.5525

            [longitude] => -74.2915

        )



    [5] => Array

        (

            [time] => 1382060855000

            [day] => 2013-10-18

            [latitude] => 38.9122

            [longitude] => 121.6022

        )



    [6] => Array

        (

            [time] => 1382060855000

            [day] => 2013-10-18

            [latitude] => 38.9122

            [longitude] => 121.6022

        )

)

里面的经纬度有重复的数据，想过滤掉重复数据，并且得到每一个相同经纬度的数量。最后得到的数组如下：


这个要怎么实现呢？ php 数组

分享到：

------解决方案--------------------

$ar = array (

  0 => 

  array (

    'time' => '1382060855000',

    'day' => '2013-10-18',

    'latitude' => '39.9289',

    'longitude' => '116.3883',

  ),

  1 => 

  array (

    'time' => '1382060855000',

    'day' => '2013-10-18',

    'latitude' => '42',

    'longitude' => '43.5',

  ),

  2 => 

  array (

    'time' => '1382060855000',