write an array (or other data) to a file in matlab

February 15th, 2006 by Lawrence David

[update: a much easier solution]save ‘my_file.name’ my_array_or_matrix -ASCII -TABS

to write a file in matlab, you first need to get a file id:

>> fid = fopen(’nameofyourfile.txt’,'w’)

(the ‘w’ means that this file will completely overwrite whatever file shares the same filename)

to write to the file, use the fprint command:

>> fprintf(fid,’%d’,5);

this puts the number 5 into nameofyourfile.txt.

to prevent the file handling gnomes from attacking you in the night, be sure to close the file when you’re finished writing all of your data:

>> fclose(fid);

Posted in Matlab |

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on 25 Apr 2008 at 6:18 am deine mutter

hi there,

isn’t it supposed to be fprintf(fid,’%d’,5); ?

greetings
on 30 Apr 2008 at 8:40 am Lawrence David

why yes it is! thanks deine! this post has been duly updated.
on 16 Jul 2008 at 2:20 pm Trevor

OOPS
you’re instructions are wrong, good sir.

>> fprintf(fid,’%d’,5);
??? fprintf(fid,’%d’,5);
|
Error: The input character is not valid in MATLAB statements or expressions.
on 24 Jul 2008 at 12:02 pm Dewey

Whats the difference between the statements? They all look the same to me. Am I missing something?
on 20 Aug 2008 at 8:34 am Lawrence David

hi trevor — you might want to check that when you copy and paste, you’re using single quotes, instead of backticks!
on 25 Sep 2008 at 10:38 am Angi

this is not really writing an array to a file. it is writing one number into a file. How do you handle the command if you’ve got an array containing cells with different formats?

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