Optimate

I want to optimate this code it couldn't work undeer Mat. 2007b, I wrote it in Mat. 2010a.could u help me plz.

function varargout = diplomarbeit(varargin)

gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @diplomarbeit_OpeningFcn, ...
                   'gui_OutputFcn',  @diplomarbeit_OutputFcn, ...
                   'gui_LayoutFcn',  [] , ...
                   'gui_Callback',   []);
if nargin && ischar(varargin{1})
    gui_State.gui_Callback = str2func(varargin{1});
end

if nargout
    [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
    gui_mainfcn(gui_State, varargin{:});
end

function diplomarbeit_OpeningFcn(hObject, eventdata, handles, varargin)

handles.output = hObject;

guidata(hObject, handles);

function varargout = diplomarbeit_OutputFcn(hObject, eventdata, handles) 

varargout{1} = handles.output;

function kurrolation_Callback(hObject, eventdata, handles)

function sin_Callback(hObject, eventdata, handles)

function cos_Callback(hObject, eventdata, handles)

function tri_Callback(hObject, eventdata, handles)

function si_Callback(hObject, eventdata, handles)

function falten_Callback(hObject, eventdata, handles)    

function rect_Callback(hObject, eventdata, handles)

function funk_SelectionChangeFcn(hObject, eventdata, handles)

        global y

        t=0:0.01:2*pi;

          switch get(hObject,'Tag')                      

              case 'sin'
                y=sin(t);

              case 'cos'
                y=cos(t);

              case 'tri'
                y = tripuls(t);

              case 'si'    
               y = sin(4*t-2*t)./t;          

              case 'rect'
                y=rectpuls(t); 

%             otherwise

          end

          axes(handles.signal);
          plot(t,y);
          grid on;

function startbutton_Callback(hObject, eventdata, handles)

           global y

              yf=conv(y,y);

%             laenge=size(yf)
%             d=laenge(2)-1
%             tf=linspace(0,laenge(2)-1,laenge(2))

              axes(handles.kontinuierlich);

              plot(yf);
              grid on;

function korrelationbutton_Callback(hObject, eventdata, handles)

          global y

              yf=fft(y);

%             laenge=size(yf)
%             d=laenge(2)-1
%             tf=linspace(0,laenge(2)-1,laenge(2))

              axes(handles.diskrete);
              plot(yf);
              grid on;

[Sargondjani]

you have to be more specific. what is working, what is not? what is your problem? what is the error message, if any? (provide whole error message, and repeat the line in which it occured)