how to export a 2 dimensional cell array of strings with different lengths to an excel file?

I understand XLSwrite only takes matrices. I cannot use matrices since every element is a string with different sizes

Answer 1

[Walter Roberson]

On MS Windows systems with Excel installed, xlswrite() is happy to take cell arrays. From the documentation:

"A: Input matrix, specified as a two-dimensional numeric or character array, or, if each cell contains a single element, a cell array.

If A is a cell array containing something other than a scalar numeric or a string, then xlswrite silently leaves the corresponding cell in the spreadsheet empty."

On MS Windows system that do not have Excel installed, and on OS-X and Linux systems, you are restricted to 'basic' mode, which does have a limitation of only supporting numeric data and csv output.

On those systems, if csv is acceptable, and for the case where A is a cell array containing only strings (and any empty entries are the empty string '' instead of the empty numeric []), then

fmt = [repmat('%s,', 1, size(A,2)), '%s\n'];
fid = fopen('YourOutput.csv', 'wt');
A_flip = A.';    %transpose needed
fprintf(fid, fmt, A_flip{:});
fclose(fid);

If you have a mix of strings and numeric values then more work is required to get the right output (especially if you have datenum or datetime values to be output as date strings.)