function lbskg(invarde) {
	var lbs = invarde.lbs.value;

	//  
	if ((lbs == null) || (lbs == "") || (isNaN(lbs)) || (lbs < 0)) {
		alert("NOTE: Prego inserisci il peso in pounds.");
		invarde.lbs.focus();
		invarde.lbs.select();
		return false
	}

	var lbs = Number(lbs);

	var kg = lbs * 0.45359237;
	kg = avrunda(kg,2);

	document.vikt.kg.value = kg;
	return true
}

function kglbs(invarde) {
	var kg = invarde.kg.value;

	//  
	if ((kg == "") || (isNaN(kg)) || (kg == null) || (kg < 0)) {
		alert("NOTE: Prego inserisci il peso in Kg.");
		invarde.kg.focus();
		invarde.kg.select();
		return false
	}

	var kg = Number(kg);

	var lbs = kg * 2.2046226;
	lbs = avrunda(lbs,2);

	document.vikt.lbs.value = lbs;
	return true
}

function cminch(invarde) {
	var cm = invarde.cm.value;

	//  
	if ((cm == null) || (cm == "") || (isNaN(cm)) || (cm < 0)) {
		alert("NOTE: Prego inserisci lunghezza in cm.");
		invarde.cm.focus();
		invarde.cm.select();
		return false
	}

	var cm = Number(cm);

	var inch = cm * 0.394;
	inch = avrunda(inch,2);

	document.vikt.inch.value = inch;
	return true
}

function inchcm(invarde) {
	var inch = invarde.inch.value;

	//  
	if ((inch == "") || (isNaN(inch)) || (inch == null) || (inch < 0)) {
		alert("NOTE: Prego inserisci lunghezza in inch.");
		invarde.inch.focus();
		invarde.inch.select();
		return false
	}

	var inch = Number(inch);

	var cm = inch * 2.54;
	cm = avrunda(cm,2);

	document.vikt.cm.value = cm;
	return true
}


function cmfeet(invarde) {
	var cm = invarde.cm.value;

	//  
	if ((cm == null) || (cm == "") || (isNaN(cm)) || (cm < 0)) {
		alert("NOTE: Prego inserisci lunghezza in cm.");
		invarde.cm.focus();
		invarde.cm.select();
		return false
	}

	var cm = Number(cm);

	var feet = cm * 0.0328083989501;
	feet = avrunda(feet,2);

	document.vikt.feet.value = feet;
	return true
}

function feetcm(invarde) {
	var feet = invarde.feet.value;

	//  
	if ((feet == "") || (isNaN(feet)) || (feet == null) || (feet < 0)) {
		alert("NOTE: Prego inserisci lunghezza in piedi.");
		invarde.feet.focus();
		invarde.feet.select();
		return false
	}

	var feet = Number(feet);

	var cm = feet * 30.48;
	cm = avrunda(cm,2);

	document.vikt.cm.value = cm;
	return true
}

function Ouncesgr(invarde) {
	var Ounces = invarde.Ounces.value;

	//  
	if ((Ounces == null) || (Ounces == "") || (isNaN(Ounces)) || (Ounces < 0)) {
		alert("NOTE: Prego inserisci il peso in Ounces.");
		invarde.Ounces.focus();
		invarde.Ounces.select();
		return false
	}

	var Ounces = Number(Ounces);

	var gr = Ounces * 28.3495231;
	gr = avrunda(gr,2);

	document.vikt.gr.value = gr;
	return true
}

function grOunces(invarde) {
	var gr = invarde.gr.value;

	//  
	if ((gr == "") || (isNaN(gr)) || (gr == null) || (gr < 0)) {
		alert("NOTE: Prego inserisci il peso in gr.");
		invarde.gr.focus();
		invarde.gr.select();
		return false
	}

	var gr = Number(gr);

	var Ounces = gr * 0.0352739;
	Ounces = avrunda(Ounces,2);

	document.vikt.Ounces.value = Ounces;
	return true
}


function avrunda(number,decimal) {
        multiplier = Math.pow(10,decimal);
        number = Math.round(number * multiplier) / multiplier;
        return number
}