public function modificarNumeroMatricula()
 {
     try {
         if ($this->verificarSession()) {
             $arreglo = isset($_POST['matriculas']) ? $_POST['matriculas'] : NULL;
             $matriculas = json_decode($arreglo);
             $matricula = new Matricula();
             $fecha = getdate();
             $Alectivo = $fecha["year"];
             if ($fecha["month"] == "December") {
                 $Alectivo++;
             }
             foreach ($matriculas as $mat) {
                 $matricula->modificarNMatricula($mat[0], $mat[1], $Alectivo);
             }
             echo json_encode(1);
         }
     } catch (Exception $exc) {
         echo $exc->getTraceAsString();
     }
 }