function testDig(e) {
  var key = (typeof e.charCode == 'undefined' ? e.keyCode : e.charCode); 	// Make sure to use event.charCode if available
  if (e.ctrlKey || e.altKey || key < 32) return true;											// Ignore special keys
	var re = /[\d\.\-\+]/;
  key = String.fromCharCode(key);
  if (re.test(key)) return re.test(key);
  else {
  	alert("Only digits, minus sign and decimal point is allowed!");
  	return false;
  }
}
function testNum(obj, cutOff) {
  if (isNaN(obj.value)) {
  	obj.value = "0.0";
  	alert("This is not a number! The value was reset.");
  	return false;
  } else if (Math.abs(obj.value) > cutOff) {
  	obj.value = "0.0";
  	alert("This exceeds the specified boundary! The value was reset.");
  	return false;
  }
  else return true;
}