Question

I’m trying to sort an array by value descending keeping keys (arsort), but if the values are equal I want it also sorted in order of keys ascending (ksort).

I’ve been trying this:

ksort($array);
arsort($array);

But the ksort is not kept, and the keys get jumbled up again after the arsort.

E.g. if my input array in:

$array[0] = 4;
$array[1] = 2;
$array[2] = 3;
$array[3] = 1;
$array[4] = 4;

I want to sort it so it ends like this:

$array[0] = 4;
$array[4] = 4;
$array[2] = 3;
$array[1] = 2;
$array[3] = 1;

NOT like this:

$array[4] = 4;
$array[0] = 4;
$array[2] = 3;
$array[1] = 2;
$array[3] = 1;

But the previous order of the keys appears to be disturbed by arsort.

Answer 1

PHP dropped stable sorting (which guaranteed the ordering you wanted) in PHP 4.1:
https://bugs.php.net/bug.php?id=53341&edit=1

Here’s a seemingly dupe question, with a code snippet, to work around it (basically: write your own sort function. Boo.):
Preserve key order (stable sort) when sorting with PHP's uasort