how can i give the variable of a slider to another function?

Hello,

sorry for my bad english..

I have created four Sliders in gui, and show their value in an edit text box.

Now i want to use the four variables of the slider (var1, var2, var3 und var4) in an other function to plot a graph.

In the function "function out = chua_function(t,p)" i want to write "a = var1, b = var2,.." instead of "a =16, b = 1,.."

how can i do this? i have tried this with global variables, but it don't worked.

Heres my code:

function varargout = chaos_simulation_gui(varargin)
% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name', mfilename, ...
'gui_Singleton', gui_Singleton, ...
'gui_OpeningFcn', @chaos_simulation_gui_OpeningFcn, ...
'gui_OutputFcn', @chaos_simulation_gui_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
 
function chaos_simulation_gui_OpeningFcn(hObject, eventdata, handles, varargin)
[t,y] = ode45(@chua_function,[0 150],[1 0 0]);
axes(handles.axes1);
plot3(y(:,1),y(:,2),y(:,3)) %3D Plot
xlabel('D^-^1 Region')
ylabel('D^0 Region')
zlabel('D^1 Region')
grid
... 
% Choose default command line output for chaos_simulation_gui
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);

% --- Outputs from this function are returned to the command line.
function varargout = chaos_simulation_gui_OutputFcn(hObject, eventdata, handles)
% Get default command line output from handles structure
varargout{1} = handles.output;

function slider_a_Callback(hObject, eventdata, handles)
val1=get(hObject,'value');
set(handles.edit1,'string',num2str(val1));
guidata(hObject,handles);

function slider_a_CreateFcn(hObject, eventdata, handles)
if isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
set(hObject,'BackgroundColor',[.9 .9 .9]);
end

...

function slider_n_Callback(hObject, eventdata, handles)
val4=get(hObject,'value');
set(handles.edit4,'string',num2str(val4));
guidata(hObject,handles);

function slider_n_CreateFcn(hObject, eventdata, handles)
if isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
set(hObject,'BackgroundColor',[.9 .9 .9]);
end

function edit1_Callback(hObject, eventdata, handles)
value1=get(hObject,'string');
set(handles.text,'value',num2str(value1));
guidata(hObject,handles);

function edit1_CreateFcn(hObject, eventdata, handles)
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
set(hObject,'BackgroundColor','white');
end
 
...
function edit4_Callback(hObject, eventdata, handles)
value4=get(hObject,'string');
set(handles.text,'value',num2str(value4));
guidata(hObject,handles);

function edit4_CreateFcn(hObject, eventdata, handles)
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
set(hObject,'BackgroundColor','white');
end

function out = chua_function(t,p)
a = 16; % here i want to write a = val1
B = 30; % here i want to write b = val2
m = -1.2; 
n = -0.7;
x = p(1);
y = p(2);
z = p(3);

g = n*x+0.5*(m-n)*(abs(x+1)-abs(x-1)); %St�ckweise Lineare Gleichung der Diode
xdot = a*(y-x-g);
ydot = x - y+ z;
zdot = -B*y;
out = [xdot ydot zdot]';

Answer 1

[Bhaskar R]

In the end of evert UI control funtion make a statement as

guidata(hObject,handles);    % which enables the to pass/updates varibles

Then modify your function as

Your required data variables var1, var2, var3 and var4 already globally visiable with the GUI handles as in the edit boxes(you have set in each UI control of slider) so you need to modify in the called/defination function as

function out = chua_function(hObject,handles)
% you need to get variables from handles 
val1 = str2num(handles.edit1.String);
val2 = str2num(handles.edit2.String);
val3 = str2num(handles.edit3.String);
val4 = str2num(handles.edit4.String);
% a = 16; % here i want to write a = val1
% then
a = val1;
% B = 30; % here i want to write b = val2
B = val2;
m = -1.2; 
n = -0.7;
 
x = p(1);
y = p(2);
z = p(3);
 
g = n*x+0.5*(m-n)*(abs(x+1)-abs(x-1)); %St�ckweise Lineare Gleichung der Diode
xdot = a*(y-x-g);
ydot = x - y+ z;
zdot = -B*y;
out = [xdot ydot zdot]';
guidata(hObject,handles);

[Rik]

Comment posted as answer by Albin Troglauer:

I have changed my code like you sayd.

Now the mistake is:

"Dot indexing is not supported for variables of this type.

Error in chaos_simulation_gui>chua_function (line 165)

val1 = str2num(handles.edit1.String);

"

function varargout = chaos_simulation_gui(varargin)
% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @chaos_simulation_gui_OpeningFcn, ...
                   'gui_OutputFcn',  @chaos_simulation_gui_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
function chaos_simulation_gui_OpeningFcn(hObject, eventdata, handles, varargin)
[t,y] = ode45(@chua_function,[0 150],[1 0 0]);        
axes(handles.axes1);
plot3(y(:,1),y(:,2),y(:,3)) %3D Plot
xlabel('D^-^1 Region')
ylabel('D^0 Region')
zlabel('D^1 Region')
grid
axes(handles.axes2);
plot(y(:,1),y(:,2)) %2D Plot (D-1/D0 Bereich)
xlabel('D^-^1 Region')
ylabel('D^0 Region')
grid
axes(handles.axes3);
plot(y(:,2),y(:,3)) %2D Plot (D0/D1 Bereich)
xlabel('D^0 Region')
ylabel('D^1 Region')
grid
axes(handles.axes4);
plot(y(:,1),y(:,3)) %2D Plot (D-1/D1 Bereich)
xlabel('D^-^1 Region')
ylabel('D^1 Region')
grid
% Choose default command line output for chaos_simulation_gui
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);
% --- Outputs from this function are returned to the command line.
function varargout = chaos_simulation_gui_OutputFcn(hObject, eventdata, handles) 
% Get default command line output from handles structure
varargout{1} = handles.output;
function slider_a_Callback(hObject, eventdata, handles)
global val1;
val1=get(hObject,'value');
set(handles.edit1,'string',num2str(val1));
guidata(hObject,handles);
function slider_a_CreateFcn(hObject, eventdata, handles)
if isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor',[.9 .9 .9]);
end
function slider_b_Callback(hObject, eventdata, handles)
val2=get(hObject,'value');
set(handles.edit2,'string',num2str(val2));
guidata(hObject,handles);
function slider_b_CreateFcn(hObject, eventdata, handles)
if isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor',[.9 .9 .9]);
end
function slider_m_Callback(hObject, eventdata, handles)
val3=get(hObject,'value');
set(handles.edit3,'string',num2str(val3));
guidata(hObject,handles);
function slider_m_CreateFcn(hObject, eventdata, handles)
if isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor',[.9 .9 .9]);
end
function slider_n_Callback(hObject, eventdata, handles)
val4=get(hObject,'value');
set(handles.edit4,'string',num2str(val4));
guidata(hObject,handles);
function slider_n_CreateFcn(hObject, eventdata, handles)
if isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor',[.9 .9 .9]);
end
function edit1_Callback(hObject, eventdata, handles)
value1=get(hObject,'string');
set(handles.text,'value',num2str(value1));
guidata(hObject,handles);
function edit1_CreateFcn(hObject, eventdata, handles)
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end
function edit2_Callback(hObject, eventdata, handles)
value2=get(hObject,'string');
set(handles.text,'value',num2str(value2));
guidata(hObject,handles);
function edit2_CreateFcn(hObject, eventdata, handles)
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end
function edit3_Callback(hObject, eventdata, handles)
value3=get(hObject,'string');
set(handles.text,'value',num2str(value3));
guidata(hObject,handles);
Setappdata(hObject,'result', value3);
function edit3_CreateFcn(hObject, eventdata, handles)
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end
function edit4_Callback(hObject, eventdata, handles)
value4=get(hObject,'string');
set(handles.text,'value',num2str(value4));
guidata(hObject,handles);
function edit4_CreateFcn(hObject, eventdata, handles)
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end
function out = chua_function(hObject,handles)
% you need to get variables from handles 
val1 = str2num(handles.edit1.String);
val2 = str2num(handles.edit2.String);
val3 = str2num(handles.edit3.String);
val4 = str2num(handles.edit4.String);
% a = 16; % here i want to write a = val1
% then
a = val1;
% B = 30; % here i want to write b = val2
B = val2;
m = -1.2; 
n = -0.7;
 
x = p(1);
y = p(2);
z = p(3);
 
g = n*x+0.5*(m-n)*(abs(x+1)-abs(x-1)); %St�ckweise Lineare Gleichung der Diode
xdot = a*(y-x-g);
ydot = x - y+ z;
zdot = -B*y;
out = [xdot ydot zdot]';
guidata(hObject,handles);

[Rik]

If you are using an old version of Matlab you will need to use get instead of the dot syntax:

val1 = str2num(get(handles.edit1,'String'));
%etc

Also, since you don't modify anything in the handles struct, storing that variable back to the GUI figure doesn't do anything. global variables should be avoided (especially with very short names like var1).

It also looks like you want to affect the function with the values from the sliders. This will not happen, unless you move the call to ode45 out of the opening function.

[Rik]

Comment posted as answer by Albin Trog:

Sorry but I am completely new in Matlab.. How must I modify anything in the handles struct? Yes, I want to affect the function with the values from the sliders. Where must I move the ode45?

[Rik]

Please don't post your comments in the answer section.

You don't need to modify the handles struct at all.

If you want to use the values of the sliders in a function, the best way is probably to have a button. Then you can set the sliders to your chosen values and put the call to ode45 and your plotting functions in the callback function of the button. You should be aware that the OpeningFcn runs only once: when the GUI starts.

If you are confused by GUIDE: don't feel bad, it is a mess. If you are confused by Matlab, try OnRamp. For a more thorough discussion about your options when it comes to GUIs: how to create a GUI.