function CalculateVolume(frm)
{
	var vol;
	var area;
	var chosen;
	var shallowend;
	var deepend;
	var depth;
	var A;
	var B;
	var C;
	var R;
	
	for (var i = 0; i < frm.poolshape.length; i++)
	{
		if (frm.poolshape[i].checked)
		{
			chosen = frm.poolshape[i].value;
			break;
		}
	}
	
	shallowend = parseFloat(frm.shallow.value);
	deepend = parseFloat(frm.deep.value);
	depth = (shallowend + deepend) / 2;
	
	if (isNaN(depth))
	{
		alert("You must fill in the deep end and shallow end depths.")
		return;
	}
	
	switch(chosen)
	{
		case "rectangle":
			A = parseFloat(frm.RA.value);
			B = parseFloat(frm.RB.value);
			area = A * B;
			break;
		case "oblong":
			A = parseFloat(frm.OA.value);
			B = parseFloat(frm.OB.value);
			C = parseFloat(frm.OC.value);
			area = (A + B) * C * .45;
			break;
		case "circle":
			R = parseFloat(frm.CR.value);
			area = R * R * Math.PI;
			break;
		case "triangle":
			A = parseFloat(frm.TA.value);
			B = parseFloat(frm.TB.value);
			area = A * B / 2;
	}
	vol = area * depth * 7.5;
	
	if (isNaN(vol))
	{
		alert("You must fill in all the fields for the chosen pool shape.")
	}
	else
	{
		frm.volume.value = Math.round(vol * 100) / 100;
	}
	return;
}

function setRadioFocus(typ, frm)
{
	for (var i = 0; i < frm.poolshape.length; i++)
	{
		if (frm.poolshape[i].value == typ)
		{
			frm.poolshape[i].checked = true;
			break;
		}
	}
	return;
}