Pagi agan agan sekalian, ijin buka forum. jadi saya lagi buat program untuk generate nomer otomatis untuk surat persetujuan, saya pake (php, html dan mysql). tapi saya dapet beberapa error dan udah searching tp ga nemu yang berhubungan sama case di program saya, barangkali diantara agan agan sekalian ada yang lebih tau jadi bisa sharing ilmu untuk case problem saya.

ini kode errornya :

Notice: Undefined variable: getRomawi in C:\xampp\htdocs\bigweb\number_generate.php on line 5

Fatal error: Uncaught Error: Function name must be a string in C:\xampp\htdocs\bigweb\number_generate.php:5 Stack trace: #0 C:\xampp\htdocs\bigweb\save.php(3): require_once() #1 {main} thrown in C:\xampp\htdocs\bigweb\number_generate.php on line 5

jadi itu ada beberapa file nih gan, untuk yang error pertama (Notice : ...) ini source codenya :
--------------------------------------------------------------------------------------------------------------------
include "fungsi_romawi.php";
include "save.php";
$month = date('n');
$romawi = $getRomawi($month);
$year = date('Y');
$number = "/YMMI/".$romawi."/".$year;

$query = "SELECT MAX(number_out) as MAXKODE FROM bigdata_admin WHERE month(date_in)='$month'";
$hasil = mysqli_query($query);
$data = mysqli_fetch_array($hasil);
$no = $data['MAXKODE'];
$Gnome = $no+1;

$kode = sprintf("s", $Gnome);
$nomerbaru = $kode.$number;

--------------------------------------------------------------------------------------------------------------------
dan ini untuk error yang kedua (Fatal Error : ...) ini source codenya :
--------------------------------------------------------------------------------------------------------------------
<?php
if (!empty($_POST['signup']));
require_once "number_generate.php";

$servername = "localhost";
$username = "root";
$password = "";
$dbname = "bigdata";
{
$id_in = (FILTER_VAR($_POST['id_in'], FILTER_SANITIZE_NUMBER_INT));
$name_in = (FILTER_VAR($_POST['name_in'], FILTER_SANITIZE_STRING));
$dept_in = (FILTER_VAR($_POST['dept_in'], FILTER_SANITIZE_STRING));
$information_in = (FILTER_VAR($_POST['information_in'], FILTER_SANITIZE_STRING));
$date_in = $_POST['date_in'];

try
{
$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$stmt = $conn->prepare("INSERT INTO bigdata_admin (id_in, name_in, dept_in, information_in, date_in)
VALUES (:id_in, :name_in, :dept_in, :information_in, :date_in)");
$stmt->bindParam(":id_in", $id_in,PDO::PARAM_INT);
$stmt->bindParam(":name_in", $name_in,PDO::PARAM_STR);
$stmt->bindParam(":dept_in", $dept_in,PDO::PARAM_STR);
$stmt->bindParam(":information_in", $information_in,PDO::PARAM_STR);
$stmt->bindParam(":date_in", $date_in,PDO::PARAM_STR);
$stmt->execute();
    }
catch(PDOException $e)
    {
echo "Error: " . $e->getMessage();
    }
}
$conn = null;
?> 

--------------------------------------------------------------------------------------------------------------------
dan saya juga bikin function switch case untuk generate nomer romawi :

-------------------------------------------------------------------------------------------------------------------- 
<?php
function getRomawi($month)
{
switch($month)
{
case '1':
return "I";
break;
case '2':
return "II";
break;
case '3':
return "III";
break;
case '4':
return "IV";
break;
case '5':
return "V";
break;
case '6':
return "VI";
break;
case '7':
return "VII";
break;
case '8':
return "VIII";
break;
case '9':
return "IX";
break;
case '10':
return "X";
break;
case '11':
return "XI";
break;
case '12':
return "XII";
break;
}
}
?> 


maaf kalo kepanjangan gan, mohon pencerahannya