对象数组，提取最高值

Question

Given an array of objects stored in $my_array, I'd like to extract the 2 objects with the highest count value and place them in a separate object array. The array is structured as below.

How would I go about doing that?

array(1) { 
     [0]=> object(stdClass)#268 (3) { 
             ["term_id"]=> string(3) "486" 
             ["name"]=> string(4) "2012" 
             ["count"]=> string(2) "40"
     } 
     [1]=> object(stdClass)#271 (3) { 
             ["term_id"]=> string(3) "488" 
             ["name"]=> string(8) "One more"
             ["count"]=> string(2) "20"  
     } 
     [2]=> object(stdClass)#275 (3) { 
             ["term_id"]=> string(3) "512" 
             ["name"]=> string(8) "Two more"
             ["count"]=> string(2) "50"  
     } 

Answer 1

You can do this many ways. One rather naive way would be to use usort() to sort the array, and then pop off the last two elements:

usort($arr, function($a, $b) {
    if ($a->count == $b->count) {
        return 0;
    }

    return $a->count < $b->count ? -1 : 1
});

$highest = array_slice($arr, -2, 2);

Edit:

Note that the previous code uses an anonymous function, which is only available in PHP 5.3+. If you're using < 5.3, you can just use a normal function:

function myObjSort($a, $b) {
    if ($a->count == $b->count) {
        return 0;
    }

    return $a->count < $b->count ? -1 : 1
}

usort($arr, 'myObjSort');

$highest = array_slice($arr, -2, 2);