Can rsort and usort be used together in php arrays?

rsort() simple sorting in reverse order:

You can also use the rsort() function to sort, and its result is the same as the sort used previously. () Simple sorting results in the opposite. The Rsort() function sorts the array elements from high to low, either numerically or alphabetically.

<?php    
$data = array(5,8,1,7,2);
    rsort($data); 
    print_r($data);
?>

Its output results are as follows:

Array ([0] => 8 [1] => 7 [2] => 5 [3] => 2 [4] => 1 )

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usort() is based on user-defined Rule sorting:

PHP also lets you define your own sorting algorithm by creating your own comparison function and passing it to the usort() function. If the first parameter is "smaller" than the second parameter, the comparison function must return a number smaller than 0. If the first parameter is "larger" than the second parameter, the comparison function should return a number larger than 0. .

Listing I is an example of this, where array elements are sorted according to their length, with the shortest items first: sortByLen must be in a fixed format.

<?php    
$data = array("joe@", "@", "asmithsonian@", "jay@");
    usort($data, &#39;sortByLen&#39;);    
    print_r($data); 
function sortByLen($a, $b) {
    if (strlen($a) == strlen($b)) {
        return;
        } 
        else {
    return (strlen($a) > strlen($b)) ? 1 : -1;
    }
}?>

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