function isNumber(inputVal, obrigatorio){
	if (!obrigatorio && inputVal == "")
		return true

	numeros = "0123456789.,-"
	inputStr = inputVal.toString() 
	for (var i = 0; i < inputStr.length; i++) { 
		var oneChar = inputStr.charAt(i) 
		if (numeros.indexOf(oneChar) == -1){
			return false
		}
	} 
	return true 
}