How to show matrix data in the app.UITable.Data with every iteratoin in a loop??

I work on a project in the app designer to creat a table. I can see the table in command window but if I tried to assign it to the UITable.Data. it just does not work.

here is the funciton that I have.

                
                H(end+1,:) = {Step_Size, Power, Freq}; % Add new rows of data in the loop
                
                App.UITable.Data = table2struct(H);   % tried to convert it to struct because 

[Mario Malic]

Initialize the first row of UITable just once

app.UITable.Data = table(Step_Size, Power, Freq);

Then add the rest of the data

app.UITable.Data(end+1,:) = [Step_Size, Power, Freq]; % if these are scalars