when i am pressing the push button " show all the techniques" the image is showing all the pictures, but when I select any other push button after that it is not working. Can you please help me ?

% --- Executes on button press in pushbutton1. function pushbutton1_Callback(hObject, eventdata, handles)

axes(handles.axes1);

a=imread('butterfly.jpg');

b=rgb2gray(a);

e=edge(b,'sobel');

f=edge(b,'canny');

g=edge(b,'prewitt');

h=edge(b,'roberts');

i=edge(b,'log');

j=edge(b,'zerocross',[]);

subplot(3,2,1);imshow(e);title('SOBEL EDGE DETECTOR');

subplot(3,2,2);imshow(f);title('CANNY EDGE DETECTOR');

subplot(3,2,3);imshow(g);title('PREWITT EDGE DETECTOR');

subplot(3,2,4);imshow(h);title('ROBERTS EDGE DETECTOR');

subplot(3,2,5);imshow(i);title('LAPLACIAN OF GAUSSIAN METHOD');

subplot(3,2,6);imshow(j);title('ZERO CROSS METHOD');

% --- Executes on button press in pushbutton2. function pushbutton2_Callback(hObject, eventdata, handles)

axes(handles.axes1);

a=imread('butterfly.jpg');

imshow(a);

% --- Executes on button press in pushbutton3.

function pushbutton3_Callback(hObject, eventdata, handles)

axes(handles.axes1);

a=imread('butterfly.jpg');

b=rgb2gray(a); imshow(b);