function validQty(q) {	
	if (q.length == undefined){
		v = q.value;
		if (!isValidQuantity(v)) {
			alert("Please enter a valid quantity!")
			q.focus();
			return false;
		}

	}
	else{
		for (var x = 0;x < q.length; x++)
		{
			v = q[x].value;
			if (!isValidQuantity(v)) {
			alert("Please enter a valid quantity!")
			q[x].focus();
			return false;
			}
		}
		
	}
}


function isValidQuantity(quantity){
    if(isNaN(quantity.replace(/ /g,"")) || quantity=='' || quantity=='0' || quantity< 0){
        return false;
    } else {
        return true;
    }
}