MATLAB: Do I get NaNs when I try to enter characters in the UITABLE object

MATLAB

I create a uitable as follows:

   u=uitable('Data',cell(3,1),'ColumnEditable',[true],'ColumnFormat',{'char'});

When I attempt to type characters in the uitable, the result stored in the 'Data' property of the uitable is 'NaN' even though I had specified the column format to accept characters.

Best Answer

This is the expected behavior when there is a "mis-match" between the Data property's type and the ColumnFormat property. In the example above, Data is a numeric type (cell(3,1) creates three empty numeric matrices) but ColumnFormat is being set to 'char'. A table in the following documentation page describes the expected behavior for all the possible combination of Data types and ColumnFormat settings:

http://www.mathworks.com/help/releases/R2009b/techdoc/ref/uitableproperties.html

To avoid this mis-match, in this case you should initialize the Data property of the uitable with a cell array of empty strings as follows:

data(1:3,1) = {''};
u=uitable('Data',data,'ColumnEditable',[true],'ColumnFormat',{'char'});

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MATLAB: Using a ‘listbox’ in MATLAB R2015b, why do I receive the warning ‘Multiple-selection ‘listbox’ control requires that ‘Value’ be an integer within String range’

The error may be generated because the 'Value' property of the listbox is greater than the length of the cell array that is being assigned to the 'String' property. In other words, if the listbox has a 'Value' of 10, the cell array assigned to the 'String' property must have at least 10 elements.

To further demonstrate why the error might be occurring and to help with fixing the issue, consider the following code, which should run without errors in MATLAB R2015b:

>> MyString={'1','2','3','4','5'};
>> b=uicontrol('Style','listbox','Min',0,'Max',2,'Value',2);  % Value is less than the elements in 'MyString'
>> set(b,'String',MyString)

However, the following code will generate the error:

>> MyString={'1','2','3','4','5'};
>> b=uicontrol('Style','listbox','Min',0,'Max',2,'Value',10);  % Value is greater than the elements in 'MyString'
>> set(b,'String',MyString)

The difference between the two blocks of code above is that the second block of code has a 'Value' that is greater than the number of elements in the string.

MATLAB: Is it possible to control the precision of a numeric value displayed in a UITABLE in MATLAB 7.6 (R2008a)

The ability to control the precision of a number in UITABLE, besides using the FORMAT function, is not available in MATLAB.

To work around this issue, one can use the SPRINTF function to control the precision of the numeric value displayed. As an example, consider the following code:

f = figure('Position',[100 100 400 150]);
dat =  {6.125, 456.3457, true,  'Fixed';...
        6.75,  510.2342, false, 'Adjustable';...   
        7,     658.2,    false, 'Fixed';};
columnname =   {'Rate', 'Amount', 'Available', 'Fixed/Adj'};
columnformat = {'numeric', 'bank', [], {'Fixed' 'Adjustable'}}; 
columneditable =  [false false true true]; 
t = uitable('Units','normalized','Position',...
            [0.1 0.1 0.9 0.9], 'Data', dat,... 
            'ColumnName', columnname,...
            'ColumnFormat', columnformat,...
            'ColumnEditable', columneditable);
data = get(t, 'data');
for i = 1:numel(data)
    if(isnumeric(data{i}))
        tempStr = sprintf('%2.4g', data{i});
        data{i} = tempStr;       
    end
end
set(t, 'data', data);

This creates a UITABLE and allows the user to control the precision of the numeric value using the SPRINTF function.

Best Answer

Related Solutions

MATLAB: Using a ‘listbox’ in MATLAB R2015b, why do I receive the warning ‘Multiple-selection ‘listbox’ control requires that ‘Value’ be an integer within String range’

MATLAB: Is it possible to control the precision of a numeric value displayed in a UITABLE in MATLAB 7.6 (R2008a)

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