Gui plot using Guide

Hi all,

I got some help with a code that lets me plot a variable in real time. However, I am having problem plotting 2 variables or inputs on th same plot. When I try to plot both inputs, it somehow combines the value and plots a single point for both. Not as famaliar with this plot method and not a 100% sure if it's even possible to do what I'm trying to.

Does you all have suggestions or other things to try?

Please let me know.

Thanks.

% --- Executes on button press in pushbutton2.
function pushbutton2_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

handles.edit1.String = str2double(string(handles.dev.Query('SENS1:CORR:OFFS?'))); %Grab channel offset
handles.edit2.String = str2double(string(handles.dev.Query('SENS2:CORR:OFFS?'))); %Grab channel offset

grab_max = [];
grab_max_time = datetime();

hPlot = plot(NaN, NaN, '--*');
hasPlotBeenUpdated = false;

while handles.pushbutton2.Value == 1
    grab_max= strsplit((string(handles.dev.Query('FETC1:ARR:CW:POW?'))),','); %Fetch data from PM and convert to string
    grab_max = str2double(grab_max(4)); %Average Power - Convert String to Number and place in array
    grab_max_time = datetime('now'); 
    grab_max_t = datenum(grab_max_time);
    pause(str2double(handles.edit3.String))
    hold on
    
    if ~hasPlotBeenUpdated
        hasPlotBeenUpdated = true;
        set(hPlot,'XData',grab_max_t,'YData',grab_max);
        handles.grab_max = grab_max;  
    else
        xdata = [get(hPlot,'XData'), grab_max_t]; % update the x-data
        ydata = [get(hPlot,'YData'), grab_max];   % update the y-data
        set(hPlot, 'XData', xdata, 'YData', ydata);
    end
     
end 

hold off

[Adam]

"When I try to plot both inputs, it somehow combines the value and plots a single point for both"

I don't really understand what you mean by this. do you have screenshots, or some other way of explaining it? The general technique seems fine, glancing over the code, although you need a

guidata( hObject, handles )

at the bottom of your function to ensure handles.grab_max is updated properly, but that is not relevant to the particular problem you are describing as far as I can see.

[George Diamond]

Hey Adam, thanks for responding. I added the update line.

I tried forcing both input to the same plot. Please see below:

It plots another point (different value - 0 or close to 0) on the same line instead of making a second line on the same graph.

if ~hasPlotBeenUpdated
        hasPlotBeenUpdated = true;
        set(hPlot,'XData',grab_avg_t,'YData',grab_avg);
        set(hPlot,'XData',grab_avg_t,'YData',grab2_avg); % For second input
        handles.grab_avg = grab_avg;  
    else
         xdata = [get(hPlot,'XData'), grab_avg_t]; % update the x-data
        ydata = [get(hPlot,'YData'), grab_avg];   % update the y-data
        set(hPlot, 'XData', xdata, 'YData', ydata);
    end

[Adam]

Updating plots using the method above will add to the same line, that is its purpose as it is far more efficient to do this than to keep replotting the same data just with an extra point added.

If what you want is a seperate plot though then you will need another plot instruction instead.

[George Diamond]

Thanks Adam. Is that as in I need to make a second set of axes to plot to? Do you have other suggestions for what I'm trying to do, please?

[Adam]

It's up to you if you want another axes, but if you want to visualise them in the same place then you can use the same axes, just with an appropriately positioned

hold( hAxes, 'on' )

before you do a new

plot( hAxes, ... )

instruction, where hAxes is the handle of your axes.

[George Diamond]

Hey Adam, sorry to keep bugging you. I added a hold and tried to plot in the same space. I got the following. Any ideas how I can decouple them?

[Adam]

Are there supposed to be 2 plots there? I can only see one.

[George Diamond]

Well, that's the problem. They're both plotted on the same line. I tried to plot both lines on the same plot, but it combined the results. I believe the higher points are grab_max points and the lower point from grab2_max points.

[Adam]

If they are being plotted as two explicit plot instructions this should not happen, even if you are updating each one as you go using the above syntax, you should be updating 2 distinct line objects with the points for each.

[George Diamond]

Hey Adam, please see the code for the above plot below:

% --- Executes on button press in pushbutton1.
function pushbutton1_Callback(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)

handles.edit1.String = str2double(string(handles.dev.Query('SENS1:CORR:OFFS?'))); %Grab channel offset
handles.edit2.String = str2double(string(handles.dev.Query('SENS2:CORR:OFFS?'))); %Grab channel offset

grab_avg = [];
grab_avg_time = datetime();

grab2_avg = [];
grab2_avg_time = datetime();

hPlot = plot(NaN, NaN, '--*');
% hPlot2 = plot(NaN, NaN, '--o');
hasPlotBeenUpdated = false;


while handles.pushbutton1.Value == 1
    
    handles.pushbutton1.BackgroundColor = '1 1 0';
    
    grab_avg= strsplit((string(handles.dev.Query('FETC1:ARR:CW:POW?'))),','); %Fetch data from PM and convert to string
    grab_avg = str2double(grab_avg(2)); %Average Power - Convert String to Number and place in array 
    grab_avg_time = datetime('now'); 
    grab_avg_t = datenum(grab_avg_time);
    
    grab2_avg= strsplit((string(handles.dev.Query('FETC2:ARR:CW:POW?'))),','); %Fetch data from PM and convert to string
    grab2_avg = str2double(grab2_avg(2)); %Average Power - Convert String to Number and place in array 
       
    pause(str2double(handles.edit3.String))
    hold on
    
    if ~hasPlotBeenUpdated
        hasPlotBeenUpdated = true;
        set(hPlot,'XData',grab_avg_t,'YData',grab_avg);
        hold(handles.axes2, 'on')
        set(hPlot,'XData',grab_avg_t,'YData',grab2_avg);
        handles.grab_avg = grab_avg;  
    else
        xdata = [get(hPlot,'XData'), grab_avg_t]; % update the x-data
        ydata = [get(hPlot,'YData'), grab_avg];   % update the y-data
%         x2data = [get(hPlot2,'XData'), grab_avg_t]; % update the x-data
%         y2data = [get(hPlot2,'YData'), grab_avg];   % update the y-data
        set(hPlot, 'XData', xdata, 'YData', ydata);
%         set(hPlot2, 'XData', x2data, 'YData', y2data);
    end
     
    
    grab2_avg= strsplit((string(handles.dev.Query('FETC2:ARR:CW:POW?'))),','); %Fetch data from PM and convert to string
    grab2_avg = str2double(grab2_avg(2)); %Average Power - Convert String to Number and place in array
    grab2_avg_time = datetime('now'); 
    grab2_avg_t = datenum(grab2_avg_time);
    pause(str2double(handles.edit3.String))
    hold on
    
    if ~hasPlotBeenUpdated
        hasPlotBeenUpdated = true;
        set(hPlot,'XData',grab2_avg_t,'YData',grab2_avg);
        handles.grab2_avg = grab2_avg;  
    else
        xdata = [get(hPlot,'XData'), grab2_avg_t]; % update the x-data
        ydata = [get(hPlot,'YData'), grab2_avg];   % update the y-data
        set(hPlot, 'XData', xdata, 'YData', ydata);
    end
 
    
end 

handles.pushbutton1.BackgroundColor = '0.3 0.75 0.93';

hold off

guidata(hObject,handles)

[Adam]

You still only seem to have

hPlot

there and you are giving it both your grab_avg and grab_avg_t data. You need to distinct plot handles to update, one for each, if I understand correctly the result you want.

[George Diamond]

Hey Adam. I had shown the code above to show what produced the plot I showed earlier.

I updated the code as shown below and got some errors. please see below:

% --- Executes on button press in pushbutton1.
function pushbutton1_Callback(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)

handles.edit1.String = str2double(string(handles.dev.Query('SENS1:CORR:OFFS?'))); %Grab channel offset
handles.edit2.String = str2double(string(handles.dev.Query('SENS2:CORR:OFFS?'))); %Grab channel offset

grab_avg = [];
grab_avg_time = datetime();

grab2_avg = [];
grab2_avg_time = datetime();

hPlot = plot(NaN, NaN, '--*');
hPlot2 = plot(NaN, NaN, '--o');
hasPlotBeenUpdated = false;


while handles.pushbutton1.Value == 1
    
    handles.pushbutton1.BackgroundColor = '1 1 0';
    
    grab_avg= strsplit((string(handles.dev.Query('FETC1:ARR:CW:POW?'))),','); %Fetch data from PM and convert to string
    grab_avg = str2double(grab_avg(2)); %Average Power - Convert String to Number and place in array 
    
    grab_avg_time = datetime('now'); 
    grab_avg_t = datenum(grab_avg_time);
    
    grab2_avg= strsplit((string(handles.dev.Query('FETC2:ARR:CW:POW?'))),','); %Fetch data from PM and convert to string
    grab2_avg = str2double(grab2_avg(2)); %Average Power - Convert String to Number and place in array 
        
    pause(str2double(handles.edit3.String))
    hold on
    
    if ~hasPlotBeenUpdated
        hasPlotBeenUpdated = true;
        set(hPlot,'XData',grab_avg_t,'YData',grab_avg);
        hold(handles.axes2, 'on')
        set(hPlot2,'XData',grab_avg_t,'YData',grab2_avg);
        handles.grab_avg = grab_avg;  
    else
        xdata = [get(hPlot,'XData'), grab_avg_t]; % update the x-data
        ydata = [get(hPlot,'YData'), grab_avg];   % update the y-data
        x2data = [get(hPlot2,'XData'), grab_avg_t]; % update the x2-data
        y2data = [get(hPlot2,'YData'), grab_avg];   % update the y2-data
        set(hPlot, 'XData', xdata, 'YData', ydata);
        set(hPlot2, 'XData', x2data, 'YData', y2data);
    end
     
    grab2_avg= strsplit((string(handles.dev.Query('FETC2:ARR:CW:POW?'))),','); %Fetch data from PM and convert to string
    grab2_avg = str2double(grab2_avg(2)); %Average Power - Convert String to Number and place in array
    grab2_avg_time = datetime('now'); 
    grab2_avg_t = datenum(grab2_avg_time);
    pause(str2double(handles.edit3.String))
    hold on
    
    if ~hasPlotBeenUpdated
        hasPlotBeenUpdated = true;
        set(hPlot,'XData',grab2_avg_t,'YData',grab2_avg);
        handles.grab2_avg = grab2_avg;  
    else
        xdata = [get(hPlot,'XData'), grab2_avg_t]; % update the x-data
        ydata = [get(hPlot,'YData'), grab2_avg];   % update the y-data
        set(hPlot, 'XData', xdata, 'YData', ydata);
    end
 
end 

handles.pushbutton1.BackgroundColor = '0.3 0.75 0.93';

hold off

guidata(hObject,handles)

Error message shown below:

Error using matlab.graphics.chart.primitive.Line/set
Invalid or deleted object.

Error in Boonton_4500C_GUI_2_Continuous>pushbutton1_Callback (line 211)
        set(hPlot,'XData',grab_avg_t,'YData',grab_avg);

Error in gui_mainfcn (line 95)
        feval(varargin{:});

Error in Boonton_4500C_GUI_2_Continuous (line 42)
    gui_mainfcn(gui_State, varargin{:});

Error in matlab.graphics.internal.figfile.FigFile/read>@(hObject,eventdata)Boonton_4500C_GUI_2_Continuous('pushbutton1_Callback',hObject,eventdata,guidata(hObject))
 
Error while evaluating UIControl Callback.

[George Diamond]

Hey Adam, thanks so much for all your help. I've gotten it to work. I tweaked the code a little with both plot objects. I was not handles the individual objects properly at first. Thanks so much again.