Laravel 5 - Add custom Helper function in Laravel 5.1 Class

I am using Laravel 5.1.

I have a class like this-

<?php

namespace App\Http\Controllers;

use App\User;
use App\Http\Controllers\Controller;

class UserController extends Controller
{
    public function showProfile($id)
    {
        .....
        .....
        $anything = generateRandomData();
        .....
        return view('profile.data', ['data' => generateRandomData());
    }

    public function generateRandomData()
    {
        ..................
        ..................
        return $random_generated_data_array;
    }
}

So, when I use the showProfile($id) function, I am getting error like this-

Can anyone help me please?

via Chebli Mohamed