GUI - Trim vector according to slider positions

Hello

I have created a GUI with two sliders and one button. Now I want to use the slider positions to trim a data vector. I tried the following way, but I didn´t work...

My attempt: I changed the slider callback function in a way that a output (hS1) is created. Where hS1 is the slider position.

% --- Executes on slider movement.

function [hS1]=slider1_Callback(hObject, eventdata, handles)

% hObject    handle to slider1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'Value') returns position of slider
%        get(hObject,'Min') and get(hObject,'Max') to determine range of slider

load Data.mat

x=get(hObject,'value');
x_round=round(x)
set(hObject,'value',x_round);
y=(L_KnieAngle3D_orig(x_round,1));

line(x_round,y,'linestyle','none','marker','o','markeredgecolor','r');

hS1=x_round

I did the same with slider Nr. two. As next step I changed the callback function of the pushbutton and added the hS1&hS2 to the input parameters.

    % --- Executes on button press in pushbutton1.
    function pushbutton1_Callback(hS1, hS2, hObject, eventdata, handles)
    % hObject    handle to pushbutton1 (see GCBO)
    % eventdata  reserved - to be defined in a future version of MATLAB
    % handles    structure with handles and user data (see GUIDATA)

    load Data.mat

    Datavector_new=Datavector_orig(hS1:hS2);
    assignin('base','Datavector_new',Datavector_new);

But when I click the pushbutton I only get an empty matrix.

Datavector_new =
   Empty matrix: 0-by-1

Does someone have an idea what´s going wrong?

Answer 1

[Thomas]

Now I tried a second attempt.

I assigned the slider position to variables (x1,x2) in the workspace. Then I added the input variables x1,x2 and Datavector to the pushbutton1_Callback-function.

% --- Executes on slider movement.
function slider1_Callback(hObject, eventdata, handles)
% hObject    handle to slider1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'Value') returns position of slider
%        get(hObject,'Min') and get(hObject,'Max') to determine range of slider

load Data.mat

x=get(hObject,'value');
x_round=round(x);
set(hObject,'value',x_round);
y=(L_KnieAngle3D_orig(x_round,1));

set(line,'xdata',x_round,'ydata',y);

line(x_round,y,'linestyle','none','marker','o','markeredgecolor','r');

x1=x_round
assignin('base','x1',x1);

The pushbutton-function should create an new vector, called Datavector_new, with the limits x1 and x2.

% --- Executes on button press in pushbutton1.
function pushbutton1_Callback(x1, x2, Datavector, hObject, eventdata, handles)
% hObject    handle to pushbutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

Datavector_new=Datavector(x1:x2)

assignin('base','Datavector_new',Datavector_new);

But now I get the message:

Datavector_new = 
1x0 struct array with fields:
    figure1
    pushbutton1
    text3
    text1
    slider2
    slider1
    axes1
    output

Does someone have an idea what went wrong? Normally the "Datavector" should be shortened by the limits x1 and x2.