Undefined operator './' for input arguments of type 'cell'.

Hi , i am using the below command and getting the error:

date_num2 = datenum(testdates)+table2array(Data(1:end,2))./24;

Error

Undefined operator './' for input arguments of type 'cell'.

please help

[Stephen23]

Apparently the second column/variable of table Data is a cell array.

What do you expect division of a cell array to achieve? For example, what is the expected output of this division?:

C = {'hello','world',{}}
C./24

I recommend using the much simpler curly-braces syntax for accessing the content of the second column/variable:

https://www.mathworks.com/help/matlab/matlab_prog/access-data-in-a-table.html

[Md Abdur Rahman]

Try this:

date_num2 = datenum(testdates)+table2array{idx}(1:end,2)./24; % idx is index of Data in table2array cell

[Scott MacKenzie]

NN, you didn't say anything about the organization of the Data table. The problem, it seems to be, is that the 2nd column of the Data table likely contains text. The array2table function therefore produces a cell array of character strings. Hence the error message.

If the 2nd column of the Data table contains numeric data, the array2table function would yield a numeric vector and there would be no error message.

Answer 1

[Ronit]

Hi,

I understand you're encountering an error due to the use of the “element-wise division” operator ‘./’ with a cell array in MATLAB.

As it is mentioned in the comments as well, this issue arises because MATLAB's ‘./’ operator is designed for numerical arrays and cannot be directly applied to cell arrays.

It seems like the problem maybe arising when you extract data from a table using “table2array”, particularly the column “Data(1:end,2)”, it returns a cell array. If the cells within “Data(:,2)” contain numeric values, these must be converted into a numeric array format before you can perform any element-wise division

To resolve this, it's essential to work with numeric arrays for such arithmetic operations. You can use “cell2mat” to convert a cell array of numeric values to a numeric array.

Here’s how it can be resolved:

% First, convert the cell array to a numeric array if the cells contain numeric data. 
if iscell(Data{:,2}) 
    numericColumn = cell2mat(Data{:,2}); % Convert cells to numeric array 
else 
    numericColumn = table2array(Data(:,2)); % If the data is already numeric, just convert to an array 
end 

% Now perform the division by 24 and add to the serial date numbers from 'datenum' 
date_num2 = datenum(testdates) + numericColumn ./ 24; 

Please refer to the following documentations for further details:

• https://www.mathworks.com/help/matlab/ref/rdivide.html
• https://www.mathworks.com/help/matlab/ref/cell2mat.html

Hope this helps!