How can I calculate the value in imported table using App Designer?

Hello, I have basic knowledge in MATLAB. Basically, I would like to calculate the uitable in App Designer by input few values and add a new column as "new value" by using push button (calculate).From a new column, i can plot the graph. I have added the callback function. However, only xls.data can be imported but the calculate button is not working. Here my code for callback function:

% Callbacks that handle component events

methods (Access = private)

% Code that executes after component creation

function startupFcn(app)

end

% Button pushed function: ImportDataButton

function ImportDataButtonPushed(app, event)

t = readtable("densitydata.xlsx","sheet",1);

app.UITable_2.Data = t;

t.Properties.VariableNames{1} = 'Depth';

t.Properties.VariableNames{2} = 'Log Data';

app.UITable_2.ColumnName = t.Properties.VariableNames;

end

% Callback function: CalculateButton, UITable_2, UITable_2

function CalculateButtonPushed(app, event)

d = app.DrillingFluidEditField.Value;

m = app.MatrixDensityEditField.Value;

l = app.UITable_2.ColumnName{2};

n = (m-l)/(m-d);

app.UITable.Visible = n;

x = table2array(t(:,"Porosity"));

y = table2array(t(:,"Depth"));

plot(app.UIAxes,x,y);

end

% Callback function

function UITableDisplayDataChanged(app, event)

displayNewdata = app.UITable.DisplayData;

app.UITable.Visible = app.CalculateButton.ButtonPushedFcn;

end

end

Your help means a lot to me. Thank you.

Answer 1

[Omega]

Hi Aina,

There are some issues with your code. I have listed them below:

• The table "t" loaded in "ImportDataButtonPushed" is not accessible in "CalculateButtonPushed" (it's a local variable).
• "app.UITable_2.ColumnName{2}" is a string, not the data itself.
• You need to add a new column to the table, then update the "UITable_2.Data".
• You should use the updated table data for plotting.

You can refer to the following code as a reference to address these issues:

function ImportDataButtonPushed(app, event)
    t = readtable("densitydata.xlsx", "Sheet", 1);
    t.Properties.VariableNames{1} = 'Depth';
    t.Properties.VariableNames{2} = 'LogData';
    app.UITable.Data = t;
end

function CalculateButtonPushed(app, event)
    d = app.DrillingFluidEditField.Value;
    m = app.MatrixDensityEditField.Value;
    t = app.UITable.Data; % Get table from UI component
    
    % Calculate porosity
    porosity = (m - t.LogData) / (m - d);
    t.Porosity = porosity; % Add new column
    
    app.UITable.Data = t; % Update table in UI
    
    % Plot Porosity vs Depth
    plot(app.UIAxes, t.Porosity, t.Depth, '-o');
    xlabel(app.UIAxes, 'Porosity');
    ylabel(app.UIAxes, 'Depth');
    set(app.UIAxes, 'YDir', 'reverse'); % For depth plots
end

I hope it helps!