問題是：從GUIDE運行時，“除”的回調函數中有 “handles = guihandles( gcbf ) ;”時，顯示 “引用了不存在的字段 'axes1'。”，無法清除axes1中圖形。
             如果直接運行 “.fig” 文件，有“handles = guihandles( gcbf ) ;”時，顯示 “引用了不存在的字段 'axes1'。”；如果沒有“handles = guihandles( gcbf ) ;”時，顯示 “嘗試引用非結構體數組的字段。”。
            但在初次顯示圖形時，并沒有顯示 “引用了不存在的字段 'axes1' ”，一切正常。如果第二次點擊 “出”按鈕，則會顯示顯示 “引用了不存在的字段 'axes1' ”。
           請各路大神幫助解決。

function varargout = axes_clear(varargin)
% AXES_CLEAR MATLAB code for axes_clear.fig
%      AXES_CLEAR, by itself, creates a new AXES_CLEAR or raises the existing
%      singleton*.
%
%      H = AXES_CLEAR returns the handle to a new AXES_CLEAR or the handle to
%      the existing singleton*.
%
%      AXES_CLEAR('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in AXES_CLEAR.M with the given input arguments.
%
%      AXES_CLEAR('Property','Value',...) creates a new AXES_CLEAR or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before axes_clear_OpeningFcn gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to axes_clear_OpeningFcn via varargin.
%
%      *See GUI Options on GUIDE's Tools menu.  Choose "GUI allows only one
%      instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES

% Edit the above text to modify the response to help axes_clear

% Last Modified by GUIDE v2.5 01-Jun-2017 21:25:19

% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                  'gui_Singleton',  gui_Singleton, ...
                  'gui_OpeningFcn', @axes_clear_OpeningFcn, ...
                  'gui_OutputFcn',  @axes_clear_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
% End initialization code - DO NOT EDIT


% --- Executes just before axes_clear is made visible.
function axes_clear_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% varargin   command line arguments to axes_clear (see VARARGIN)

% Choose default command line output for axes_clear
handles.output = hObject;

% Update handles structure
guidata(hObject, handles);

% UIWAIT makes axes_clear wait for user response (see UIRESUME)
% uiwait(handles.figure1);


% --- Outputs from this function are returned to the command line.
function varargout = axes_clear_OutputFcn(hObject, eventdata, handles)
% varargout  cell array for returning output args (see VARARGOUT);
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Get default command line output from handles structure
varargout{1} = handles.output;


% --- Executes on button press in pushbutton3.
function pushbutton3_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton3 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

handles = guihandles( gcbf ) ;
axes(handles.axes3);
OOK_F




% --- Executes on button press in pushbutton4.
function pushbutton4_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton4 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

handles = guihandles( gcbf ) ;
axes(handles.axes3);  
cla reset

% --- Executes on button press in pushbutton5.
function pushbutton5_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton5 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

handles = guihandles( gcbf ) ;
axes(handles.axes1);
xinhaobao_F;


% --- Executes on button press in pushbutton6.
function pushbutton6_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton6 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

handles = guihandles( gcbf ) ;  
axes(handles.axes1);  
cla reset

% --- Executes on button press in pushbutton7.
function pushbutton7_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton7 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

handles = guihandles( gcbf ) ;
axes(handles.axes2);  
PPM_F;

% --- Executes on button press in pushbutton8.
function pushbutton8_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton8 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

handles = guihandles( gcbf ) ;
axes(handles.axes2);      
cla reset