function calcBMI(){

// Get Variables and validate to make sure they're numbers, 
// setting them to a value of 1 if they're not.

var weight = (isNaN(document.wcbubba.weight.value)) ? 1 : document.wcbubba.weight.value;
if (weight == 0) alert("Results will be inaccurate.  Weight is not a valid number.");
var height = (isNaN(document.wcbubba.height.value)) ? 1 : document.wcbubba.height.value;
if (height == 0) alert("Results will be inaccurate.  Height is not a valid number.");

// set multipliers based on whether metric or English units were selected

var wmult = (document.wcbubba.units.value == "pounds") ? 2.204 : 1;

// Turns inches/centimeters into meters

var hmult = (document.wcbubba.hunits.value == "inches") ? .0254 : .01;

// Do the calculation (weight in kg divided by the height in meters 
// times itself). The multiplication by 10 and then division by ten
// work in conjunction with Math.round() to round the value to one
// decimal place of precision.

var BMI = Math.round(((weight / wmult)/((height * hmult)*(height * hmult))) *10)/10;

// get the analysis - note this is for general purpose, there is a separate scale for
// Southeast Asian people and there may be more variants on the way

var result = "";
if(BMI < 16.5) result = "severely underweight";
else if((BMI >=16.5)&&(BMI<=18.49)) result = "underweight";
else if((BMI >=18.5)&&(BMI<=25)) result = "normal";
else if((BMI >=25.01)&&(BMI<=30)) result = "overweight";
else if((BMI >=30.01)&&(BMI<=35)) result = "obese";
else if((BMI >=35.01)&&(BMI<=40)) result = "clinically obese";
else result = "morbidly obese";


document.getElementById('results').innerHTML = "Your Body Mass Index (BMI) is: " + BMI + ".<br><br>This would be considered " + result + ".";


}