Matlab - Como detener un loop con un boton

s=get(handles.togglebutton2,'Value');

function varargout = toggle_button_caballero2(varargin)

gui_Singleton = 1;

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

                   'gui_Singleton',  gui_Singleton, ...

                   'gui_OpeningFcn', @toggle_button_caballero2_OpeningFcn, ...

                   'gui_OutputFcn',  @toggle_button_caballero2_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 toggle_button_caballero2_OpeningFcn(hObject, eventdata, handles, varargin)

global condicion

condicion=0;

handles.output = hObject;

guidata(hObject, handles);

function varargout = toggle_button_caballero2_OutputFcn(hObject, eventdata, handles)

varargout{1} = handles.output;

function togglebutton1_Callback(hObject, eventdata, handles)

global condicion

condicion=get(handles.togglebutton1,'value');

    if condicion==1

        s=0;

        while 1

            s=s+rand;

            set(handles.text2,'string', s)

            pause(0.0001)

            if condicion==0

                break;

            end

        end

    end