Why does xlswrite not replace file when I tell it to?

I have a script that uses xlswrite to export some output. I use uiputfile to prompt my user for the filename and path for this output. If a user chooses an existing file, they are ask if they want to replace the existing file.

One of my users noticed that even through he selects "replace existing file", the file is not replaced. Instead the new output is written over what was already in the file. Which creates a big old mess.

I told him the simple fix is to just delete the file ahead of time and recreate it when the script prompts him. Or just use unique filenames. He wasn't impressed with this fix and wants me to make Matlab do it for him. (My boss, so have to).

Anyone know how to do this?

Answer 1

[Walter Roberson]

uiputfile() only allows the name to be selected; it does not delete the existing file or set any flags so that routines that write files will know to overwrite the file. The code after the uiputfile() needs to delete (or rename) any existing file if the file writing code updates parts of the file.

[filename, pathstr] = uiputfile('Where do you want to write the results?');
outputfile = fullfile(pathstr, filename);
if exist(outputfile, 'file');
  delete(outputfile);
end

Answer 2

[TastyPastry]

You could fill the file with empty cells, or there's a solution here. Scroll down to the solution by ImageAnalyst.