MATLAB Answers


Save file with different extension

Asked by AsYouWish
on 11 Dec 2012


I am a newbie and am opening some files, adding some lines, then saving the files. I can't figure out how to save each file I open with a new extension while keeping the filename the same.

Here is how I am opening the files:

[FileName,PathName] = uigetfile('*.*','Select File to Plot',DefaultFile); %choose file to open.
%%%% **************** Read the File ************* 

To save the file do I use the following fopen and if so what do I put where the question marks are?

fileID = fopen(??????,'w');



1 Answer

Answer by Image Analyst
on 11 Dec 2012
 Accepted answer

You have another fopen() to open an output file. Your question marks should be replaced by the full file name of your output file. You can use sprintf() (if needed) and fullfile() to create that output file name. Then use fprintf to write text to it. Then call fclose() to close the two files.


Image Analyst
on 11 Dec 2012

I'd do

[folder, oldBaseName, oldExt] = fileparts(oldFileName);
newBaseName = sprintf('%s.txt',oldBaseName);
newFullFuleName = fullfile(folder, newBaseName);
on 11 Dec 2012

Thanks. I used that and it makes it easier to identify original and new file names when looking at the code.

Jan Simon
on 12 Dec 2012

@AsYouWish: Please accept this answer, if it solves your problem. Thanks.

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