function calcul_convertor_rapid()
	{if (document.getElementById("x1").value != "" )
			{	rez_exact = parseFloat(document.getElementById("x1").value) * parseFloat(document.getElementById("c1").value) / parseFloat(document.getElementById("c2").value);
				document.getElementById("rez").value = Math.round(rez_exact*100)/100;
				document.getElementById("tva").value = Math.round(rez_exact*100*0.24)/100;
				document.getElementById("rez_final").value = Math.round(rez_exact*100*1.24)/100;
			}	else { document.getElementById("rez").value = "";
				       document.getElementById("tva").value = "";
				       document.getElementById("rez_final").value = "";
			       }
	}