MATLAB Answers

fprintf output line break

2,692 views (last 30 days)
Hi all,
I am writing a code where under a string is generated and stored in an array.
After the array is stored, I use fprintf to write the array into an data file, and then later on the string within the array is replaced within a new string and the cycle repeats.
The problem I am having is that I have been unable to make each fprintf cmd to print in a new line in the output file so I get something looking like this:
dataline dataline dataline dataline dataline dataline dataline
...instead of this:
dataline
dataline
dataline
dataline
dataline
I've been tinkering with formatting but I still can't get it right. Can any one help me?
Thanks!!!

  1 Comment

Joao Linhares
Joao Linhares on 10 Nov 2016
On my side it worked by:
fprintf(fid, '%s', thestring);
fprintf(fid,'\n');
So basically if you split the code it works better.
Cheers

Sign in to comment.

Accepted Answer

Walter Roberson
Walter Roberson on 4 Aug 2012
fprintf(fid, '%s\n', TheString);

  3 Comments

Nikolay Rodionov
Nikolay Rodionov on 4 Aug 2012
I tried this already and it did not work for some reason. Can you think of another way?
Midhulesh Vellanki
Midhulesh Vellanki on 1 Nov 2017
This works, but open your file in Notepad++ or other application, default windows application does not represent the correct format, sometime shows new line as a space.
Walter Roberson
Walter Roberson on 22 Feb 2019
On Windows, when you fopen() your file then use 'wt' instead of just 'w' to force CR+NL to be output instead of just NL

Sign in to comment.

More Answers (4)

Image Analyst
Image Analyst on 4 Aug 2012
Try
fprintf(fid, '%s\n\r', TheString);
If that doesn't work try it with the n and r reversed.
fprintf(fid, '%s\r\n', TheString);
One of them should work.

  0 Comments

Sign in to comment.


Matthew Cooper
Matthew Cooper on 21 Feb 2019
If you are writing to a file recursively, you may need to substitute 'a' for 'w' on fopen:
fopen(fid,'foo.txt','w');
fprintf(fid,formatspec,text);
fclose(fid);
fopen(fid,'foo.txt','a');
fprintf(fid,formatspec,newtext);

  2 Comments

Walter Roberson
Walter Roberson on 22 Feb 2019
That would not affect the user's situation. This was a newline vs carriage-return+newline matter.
Matthew Cooper
Matthew Cooper on 22 Feb 2019
Can you suggest a better thread for my contribution? When you invert my answer for a question and ask it, you arrive here. It would have helped me, I am sure it will help someone else. Your clarification is also helpful. Cheers.

Sign in to comment.


Samu TanakaBlitch
Samu TanakaBlitch on 22 Apr 2016
I was having the same issue earlier today when i was writing the code and other solutions i found on the internet was not working so i just inserted a disp('"space"') to make it push to the next line.
(earlier it was like this)
(afterwards)
(example of working one)
fprintf( 'The peak resultant head acceleration experienced in the TC-14 crash test is %4.2f g.',peak)
disp(' ')
fprintf('The peak resultant head acceleration experienced in the HCR-16 crash test is %4.2f g.',peakhcr)
disp(' ')
fprintf('The peak resultant head acceleration experienced in the FF-15 crash test is %4.2f g.',peakff)

  1 Comment

Walter Roberson
Walter Roberson on 22 Apr 2016
You should have just put in \n
fprintf( 'The peak resultant head acceleration experienced in the TC-14 crash test is %4.2f g.\n',peak)

Sign in to comment.


Christine Itchon
Christine Itchon on 19 Jun 2020
What do you think would happen if the newline character were omitted from the fprintf statement below?
>> fprintf(‘The value is %d, for sure!\n’,4^3)

  1 Comment

Image Analyst
Image Analyst on 19 Jun 2020
Go ahead and try it.
>> fprintf('The value is %d, for sure!\n',4^3)
The value is 64, for sure!
>> fprintf('The value is %d, for sure!',4^3)
The value is 64, for sure!>>
As you can see if the final newline is omitted, the >> prompt does not happen on the next line. It happens on the same line.

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!