function calculate_mape($actual_path, $forecast_path)
{
    $actual = csv_get_load($actual_path);
    $forecast = csv_get_load($forecast_path);
    $count = 0;
    $sum = 0;
    while ($count < 168) {
        $k = ($actual[$count] - $forecast[$count]) / $actual[$count];
        //mape calculation
        if ($k < 0) {
            $k = $k * -1;
        }
        //absolute value
        $sum = $sum + $k;
        $count = $count + 1;
    }
    $mape = $sum / 168 * 100;
    return $mape;
}
 public function test_csv_get_load_false()
 {
     $result = csv_get_load('C:/xampp/file_does_not_exist.csv');
     $this->assertEquals($result[0], null);
 }