MATLAB: NaN elements during table data input – Matlab GUI

matlab guinannew valuetable

I have a simple gui with a table: three columns, all set to editable, containing texts. With an additional button I can append empty rows to the end of the table. However, every time I write something in the new, empty cells at the bottom of the table and hit enter the value automatically changes to NaN. I've figured out that if I write a numerical value in the cells, there's no problem, so because of some reason matlab handles the new cell elements as if their type would be numeric. Any ideas how to solve this? I tried to add a CellEditCallback to the object, but the value update seems to happen before the callback would be evaluated…

Best Answer

Peter - how are you creating the new row? Is each element (of it) a cell string or an empty matrix? If I create my new row like

 % get the current data
 data    = get(handles.uitable1,'Data');
 % determine the number of columns and create the new row of empty matrices
 numCols = size(data,2);
 newRow  = cell(1,numCols);
 % add the new row to data and save it to the table
 data    = [data ; newRow];
 set(handles.uitable1,'Data',data);

then I observe the same behaviour as you - each non-numeric entry is converted to NaN since all elements in my new row are empty matrices (i.e []).

But if I create the new row as a row of strings by assigning each element of newRow to a cell with an empty string as

 newRow  = cell(1,numCols);
 newRow(:) = {''};

or the simpler

 newRow = repmat({''},1,numCols);

then I am able to add both numeric and non-numeric data to the new row of the table since each element in the row is now a string.

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MATLAB: GUI ‘uitable’ with option to add rows using push button

Add button to your code of this form: handles.uitable is the handle to your uitable.

% --- 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)
data = get(handles.uitable, 'data');
data(end+1,:) = 0;
set(handles.uitable,'data',data)

Best Answer

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