app designer - dropdownmenu - plot values

Good Morning to all,

before this quesiton, i've read & search a lot, but i never found a straight answer.

background: since i've made some ELT, now i have cleaned data and I want to create an app since that plot data from file. The drop down menu is made with the rows of my csv. I've put a button "load" that performs all preliminary task in order to get data formatted.

pts = spreadsheetImportOptions("NumVariables", 6);

% Specify sheet and range
opts.Sheet = "DATA";
opts.DataRange = "A2:F6838";

% Specify column names and types
opts.VariableNames = ["YEAR", "MONTH", "STATE_NAME", "STATE_CODE", "CO2_QTY_TONNES", "TF"];
opts.VariableTypes = ["double", "double", "categorical", "categorical", "double", "double"];

% Specify variable properties
opts = setvaropts(opts, ["STATE_NAME", "STATE_CODE"], "EmptyFieldRule", "auto");

% Import the data
app.data = readtable("C:\Users\Ale\Documents\MATLAB\Datasets\Flights\CO2_emissions_by_state.xlsx", opts, "UseExcel", false);
app.data.Properties.VariableNames(5) = "co2";
app.data.Properties.VariableNames(4) = "statecode";
app.data.Properties.VariableNames(3) = "statename";
app.data.Properties.VariableNames(2) = "month";
app.data.Properties.VariableNames(1) = "year";
app.data.Properties.VariableNames(6) = "totalflights";
clear opts

Then I've declared all properties (variables) i will need.

properties (Access = private)
        ALBANIA
        ARMENIA
        AUSTRIA
        BELGIUM
        year 
        totalflights 
        sum_totalflights
        data 
        statename 

        %===Albania
        albaniaCo2Idx 
        albaniaCo2 
        albaniaY 
        
        % === Armenia
        armeniaCo2Idx 
        armeniaCo2 
        armeniaY

        % === Austria
        austriaCo2Idx 
        austriaCo2 
        austriaY

        %===== Belgium
        belgiumCo2Idx 
        belgiumCo2 
        belgiumY
    end

target: i want to plot data after changing values from dropdownmenu. I've tried several way to get there, but i can only plot the first value

       function StateDropDown_Albania(app, event)
            %===Albania
app.albaniaCo2Idx=app.data.statename=="ALBANIA";
app.albaniaCo2=app.data(app.albaniaCo2Idx,:);
app.albaniaY=groupsummary(app.albaniaCo2,"year","sum",["co2","totalflights"]);
app.year=app.albaniaY.year;
app.totalflights=app.albaniaY.sum_totalflights;
plot(app.UIAxes,app.year,app.totalflights)
grid on
       end

        % Callback function
        function StateDropDown_Austria(app, event)
             %===Austria
app.austriaCo2Idx=app.data.statename=="AUSTRIA";
app.austriaCo2=app.data(app.austriaCo2Idx,:);
app.austriaY=groupsummary(app.austriaCo2,"year","sum",["co2","totalflights"]);
app.year=app.austriaY.year;
app.totalflights=app.austriaY.sum_totalflights;
plot(app.UIAxes,app.year,app.totalflights)
        end

and so on...

after running, i can i only get the plot for one variable, but i would like to have a plot for all EU countries

any guess, indication will be appreciated

[Abderrahim. B]

Hi!

Can you describe further what data you have, what are you trying to achieve and what final plot is like ?

Thanks,

[alejandro paradiso]

Hello, i've found a csv on kaggle about flights arriving to each eu country. i can get the result programmatically with live script

austriaCo2Idx=data.statename=="AUSTRIA"; %logical indexing
austriaCo2=data(austriaCo2Idx,:); % filtering
gscatter(austriaCo2.month,austriaCo2.co2,austriaCo2.year); %gscatter for quick preview
grid on
xlabel 'Month'
ylabel 'Total Flights'
title 'Austria'
austriaY=groupsummary(austriaCo2,"year","sum",["co2","totalflights"]); %grouping data per year
plot(austriaY.year,austriaY.sum_totalflights)
grid on
xlabel 'Year'
ylabel 'Total Flights'
title 'Austria'
xticks(2010:2023)
xlim([2010 2023])
austriaM=groupsummary(austriaCo2,"month","sum",["co2","totalflights"]); %grouping data per month
plot(austriaM.month,austriaM.sum_totalflights)
grid on
title 'Austria'
xlabel 'Month'
ylabel 'Total Flights'
xticks(1:12)
xlim([1 12])

what i would like to do is to make a webapp, using a dropdown menu listing all eu countries and then plotting the same graph as per script above according to user selection.

Answer 1

[Binaya]

Hi Alejandro, 

As per my understanding, you are interested in creating an app that allows you to plot different data from an Excel file based on the selected option in a drop-down menu.

Please follow the steps given below as a possible solution to your query:

1. Begin by creating the application and loading all the necessary data.
2. Utilize the Component Library to add "Axes" and "Drop Down" components to your application's interface.
3. Within the "Drop Down" component, incorporate a callback function under the "ValueChangedFcn" category. a. This callback function will be triggered whenever an option is selected from the drop-down menu.
4. In the code section of the aforementioned "DropDownValueChangedFcn," utilize the "app.DropDown.Value" property to create conditional statements for the desired plots.
5. Following the conditional statement, employ a plot command to visualize the required data within the "Axes" component.
6. For instance, you can use the following example syntax

        plot(app.UIAxes,xdata,ydata); 

where "app.UIAxes" specifies the axes where the data will be plotted.

Please refer to below MathWorks Documentation for more details:

1. Display Graphics in App Designer: https://www.mathworks.com/help/matlab/creating_guis/graphics-support-in-app-designer.html
2. Callbacks in App Designer: https://www.mathworks.com/help/matlab/creating_guis/write-callbacks-for-gui-in-app-designer.html

I hope this helps.

Regards 

Binaya