MATLAB: Fprintf error inside function

errorfprintf

I am trying to create a log file as a txt from a program I am building. The problem is that I keep getting the "Undefined function 'fprinf' for input arguments of type 'double'." error when I try to write to it using fprintf. A sample code is shown:

fid=fopen(path,'w'); fprinf(fid,'%s \r\n',log); fclose(fid);

where path is a local string on my Computer and "log" is a character Array.

I can open the file just file, it creates the .txt file (I can see it in Windows) and a fid interger is given. But the fprtinf line gives the error mentioned above. I can enter it once into the Command Window and the "Did you mean:" Comes up and Displays the exact same command. I enter it again and it works but then it never works in my function. Am I missing something easy here?

Thanks! Dave

Best Answer

fprintf not fprinf :)

Related Solutions

MATLAB: Am I having trouble reading an ascii file in notepad that I produced using FPRINTF

Using the following syntax will open the file in text mode, allowing it to be read in notepad:

fid=fopen('out.txt','wt');
fprintf(fid,'%i\n',3);
fclose(fid)

This is because of the "t" flag in the FOPEN statement. Without the "t" flag, the ascii file produced will only print one newline character, while PC standard ASCII files expect two different characters, '/r/n'.

This can be demonstrated by the fact that the following syntax also works:

fid=fopen('out.txt','w');
fprintf(fid,'%i\r\n',3);
fclose(fid)

For more information on the FOPEN function, see:

http://www.mathworks.com/access/helpdesk/help/techdoc/ref/fopen.shtml

MATLAB: Use fprintf to write to a new file

...first I opened my source file via

fid=fopen('source.dat')
data=fscanf(fid, ...         % get the data
fid=fclose(fid);             % done w/ that file...
data=sqr(data);              % do something to it
fid=fopen('results.dat','w');  % a new output file
fprintf(fid, fmt, data);       % write it out
fid=fclose(fid);               % close it now, too...

If you need to read and write to two (or more) files simultaneously, you must keep unique variables for them--fid1 and fid2 are popular as are things like fhi and fho (file handle in/out). If you ever do something like

 fid=fopen('source.dat');
...
fid=fopen('output.dat','w');

you've just trashed the handle to source.dat and can no longer get to it--it's in limbo as it's open but your program has no valid way to communicate with it and you can't even close it cleanly other than by brute force hammer of

fclose('all')

or when Matlab itself finally closes and releases open handles.

doc fopen % and friends

Best Answer

Related Solutions

MATLAB: Am I having trouble reading an ascii file in notepad that I produced using FPRINTF

MATLAB: Use fprintf to write to a new file

Related Question