Uri Class problem

[eluser]Ngulo[/eluser]
hi all i have a controller (downloads.php) with this function (templates) after the main index():

Code:

function templates()
        {
          
             $tab_from_uri=$this->uri->segment(3);
                switch($tab_form_uri)
                {
                    case "1":
                        $tab = "tab1";
                    break;
                    case "2":
                        $tab = "tab2";
                    break;
                    case "3":
                        $tab ="tab3";
                    break;
                }
               $data['asd']=$this->db->order_by("data_templx","asc")->get(''.$tab);
               $this->load->view('downloads_view',$data);
            
        }

my links are

Code:

anchor('downloads/templates','List')
so they took me rightly to /index.php/downloads/templates/3 ...as i want

but,when i click the link ,loading the view,i take this error:

Code:

Message: Undefined variable: tab_form_uri

i can't find any error,i've prooved also changing uri->segment(3) to uri->segment(4)......this is not the problem i guess

any suggestions?