controller

function quote()
      {
            $this->auth->restrict();
            // load model 'admin_model'
            $this->load->model('root_model');
            $id = $this->input->post('id_user');
            $data = array('User_Quote'      => $this->input->post('quote')
                          );
            $this->root_model->update_quote($id,$data);

            redirect("root/user");
      }