Matlab - Reformulación duda popupmenu

function varargout = popumenu1(varargin)

gui_Singleton = 1;

gui_State = struct('gui_Name',       mfilename, ...

                   'gui_Singleton',  gui_Singleton, ...

                   'gui_OpeningFcn', @popumenu1_OpeningFcn, ...

                   'gui_OutputFcn',  @popumenu1_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 popumenu1_OpeningFcn(hObject, eventdata, handles, varargin)

a={'mama';'papa';'julios'; 'juan'}

b(1,1)={'nombres'};

for i=1:length(a)

b(i+1,1)=a(i);

end

b

set(handles.popupmenu1','string',a)

set(handles.popupmenu2','string',b)

whos

handles.output = hObject;

guidata(hObject, handles);

function varargout = popumenu1_OutputFcn(hObject, eventdata, handles)

varargout{1} = handles.output;

function popupmenu1_Callback(hObject, eventdata, handles)

function popupmenu2_Callback(hObject, eventdata, handles)

EJECUCION

>> popumenu1

a =

    'mama'

    'papa'

    'julios'

    'juan'

b =

    'nombres'

    'mama'

    'papa'

    'julios'

    'juan'

  Name           Size            Bytes  Class     Attributes

  a              4x1               484  cell

  ans            5x1               610  cell

  b              5x1               610  cell

  eventdata      0x0                 0  double

  hObject        1x1                 8  double

  handles        1x1               736  struct

  i              1x1                 8  double

  varargin       0x0                 0  cell