Check form input for number

[aeroswat]

I'm trying to check to see if an input value is a number (either integer or float) and then if it is a number convert it to a decimal. Unfortunately both is_numeric() and form_input_is_numeric() is not working for me...

 

here's the code i've tested

 

	function changeValue(ctrl) {
	val=ctrl.value;
	alert('1');
	if(is_numeric(val)) {
		alert("got here");
		ctrl.value = val.toFixed(2);
	}
	if(!update('value',ctrl.value)) {
		ctrl.value = vstr;
	}
}

 

It shows the first alert but when typing a 4 in the input box it does not alert got here and the function stops working.