Something

$delta = 0.9-1.0;
//$delta = -0.1;
echo $delta.'<br />';
				
				if(abs($delta)>=0.1)
				{
					if($delta<0)
						$tendance = -1;
					else
						$tendance = 1;
				}
				else
					$tendance = 0;
echo $tendance;