function getBMI() {
    if (document.getElementById('system2').checked == true) {
        var height = document.bmiform2.height.value;
        var weight = document.bmiform2.weight.value;
		height = height / 100;
		var bmi = weight / (height*height);
    }else{
        var lbs = document.bmiform.lbs.value;
        var feet = document.bmiform.feet.value;
        var inch = document.bmiform.inch.value;
        var height = (12*feet) + (inch*1);
		var bmi = (lbs*703) / (height*height);
	}
			if (bmi < '1' || isNaN(bmi) || bmi == 'Infinity') {
		        document.getElementById("bmi-result2").innerText = "";
		        document.getElementById("bmi-result").innerText = "Please tell me your height and weight.";
			}else{
			    bmi = bmi.toFixed(2);
			    if (bmi < 18.5) { var add = "Your weight is under the normal."; }
			    else if (bmi < 25) { var add = "Your weight is normal."; }
			    else if (bmi < 30) { var add = "Your weight is over the normal."; }
			    else { var add = "You are obesed."; }
                var echo = "Your BMI (Body Mass Index) is " + bmi + ".";
		        document.getElementById("bmi-result").innerText = echo;
				document.getElementById("bmi-result2").innerText = add;
			}
}

function toggleLayer(layer) {
    if (layer == 'bmi') { 
        document.getElementById('bmi').style.display = 'block';
        document.getElementById('bmi2').style.display = 'none';
    }else{
        document.getElementById('bmi').style.display = 'none';
        document.getElementById('bmi2').style.display = 'block';
    }
}

function openpopup(page) {
    window.open(page,'popjack','toolbar=no,location=no,directories=no,status=no,menubar=no,resizable=no,copyhistory=no,scrollbars=yes,width=640,height=265');
}