skeleton/sort_array_by_key.php

<?php

function sort_array_by_key($mydata, $keyname)
{
    for ($i=0; $i<count($mydata); $i++)
    {
        $swapped = false;
        for ($j=$i+1; $j<count($mydata); $j++)
        {
            if ($mydata[$i][$keyname] > $mydata[$j][$keyname])
            {
                $swapped = true;             
                $temp = $mydata[$i];
                $mydata[$i] = $mydata[$j];
                $mydata[$j] = $temp;
            }
        }
        if (!$swapped) break;
    }
    return($mydata);
}

function test_sort_array_by_key()
{
    $passing = true;
    
    $input = array( array('a' => 2, 'b' => 1), array('a' => 3, 'b' => 2), array('a' => 1, 'b' => 3) );
    $expected = array( array('a' => 1, 'b' => 3), array('a' => 2, 'b' => 1), array('a' => 3, 'b' => 2) );
    $output = sort_array_by_key($input, 'a');
    
    if ($output != $expected)
    {
        debug("Array didn't sort properly.", __FILE__, __LINE__);
        debug("  Input:    " . var_export($input, true), __FILE__, __LINE__);
        debug("  Expected: " . var_export($expected, true), __FILE__, __LINE__);
        debug("  Output:   " . var_export($output, true), __FILE__, __LINE__);
        $passing = false;
    }     
    
    return($passing);
}