<?php

	$a[] = 'test';
	$a[] = 'test2';
	$a[] = 'test3';
	
	print_r($a);
?>

Ca marche, mais voici cqui marche pas:

<?php 

//some code
                while($col = $db->fetchArray($resultat))
		{
			$thedate[] = $col['date'];
			$temperature[] = $col['temperature'];
			$counter++;
		}

//some other..
?>