Test for multi-dimensional array search optimization

Looping.php

<?php
$loops = 1000000;
$index_array = array(
	'Mr. Giggles' => 'first',
	'Lucky Pete' => 'second',
	'door' => 'third',
	'bar' => 'fourth',
	'Marius' => 'fifth',
);
$array = array(
	'first' => array(
		'type' => 'cat',
		'name' => 'Mr. Giggles',
		'age'  => 3,
	),
	'second' => array(
		'type' => 'dog',
		'name' => 'Lucky Pete',
		'age'  => 2,
	),
	'third' => array(
		'type' => 'door',
		'name' => 'door',
		'age'  => 1,
	),
	'fourth' => array(
		'type' => 'foo',
		'name' => 'bar',
		'age'  => 'baz',
	),
	'fifth' => array(
		'type' => 'giraffe',
		'name' => 'Marius',
		'age'  => 7,
	),
);

$start = microtime( TRUE );

for ( $i = 0; $i < $loops; $i++ )
{
	foreach ( $array as $number => $item )
	{
		if ( 'bar' == $item['name'] )
		{
			$test = $number;
			break;
		}//end if
	}//end foreach
}//end for

$total = microtime( TRUE ) - $start;
$avg = $total / $loops;

echo "Average for foreach with break: {$total}s ( {$avg}s per iteration)\n";

$start = microtime( TRUE );

for ( $i = 0; $i < $loops; $i++ )
{
	while ( list( $number, $item ) = each( $array ) && empty( $test ) )
	{
		if ( 'bar' == $item['name'] )
		{
			$test = $number;
		}//end if
	}//end while
}//end for

$total = microtime( TRUE ) - $start;
$avg = $total / $loops;

echo "Average for while with conditional: {$total}s ( {$avg}s per iteration)\n";


$start = microtime( TRUE );

for ( $i = 0; $i < $loops; $i++ )
{
	if ( isset( $index_array['bar'] ) )
	{
		$test = $array[ $index_array['bar'] ];
	}//end if
}//end for

$total = microtime( TRUE ) - $start;
$avg = $total / $loops;

echo "Average for isset: {$total}s ( {$avg}s per iteration)\n";