How to code fprintf on multiple lines ?

Hi,

I'm trying to write an fprintf statement on multiple lines of code so that i don't exceed a 85 columns boundary (half my screen).

I can't find a solution that don't need to use another function (like strcat) :

fprintf(strcat("Les données des deux sessions de '%s' semblent venir de",...
    " deux distributions différentes.\n p = %4.3f \n"), results_name{i}, pp);

When I try

fprintf(["Les données des deux sessions de '%s' semblent venir de"...
    " deux distributions différentes.\n p = %4.3f \n"], results_name{i}, pp);

I get an error :

% Error using fprintf
% Invalid file identifier.  Use fopen to generate a valid file identifier.

Do I really need to use a function to do so, or is there another way ?

Thank you !

Answer 1

[Rik]

As far as I'm aware this should work with strings as well, but I frequently use a setup like this with a char array instead. So if you replace double quotes by single quotes this should work with a square bracket without requiring a call to strcat.

[Carrillo Pablo]

Oh thanks it worked ! I don't quite understand why but nvm :)

fprintf(['Les données des deux sessions de ''%s'' semblent venir',...
    'd''une même distribution.\n p = %4.3f \n'], results_name{i}, pp);

[Rik]

The problem with your original code is that it generates a 1x2 string array as the FormatSpec. I can't find in the doc how you can expect fprintf to handle a non-char non-scalar FormatSpec, but I think we have the conclusion: poorly. It might attempt to treat the first string element as the fid and the second as FormatSpec, but I'm not aware of a robust way to test this hypothesis.

Also, the square bracket might be calling strcat (instead of cat) for char inputs. The debugger on my copy of R2019a doesn't allow me to step into this operation.

[Carrillo Pablo]

Thanks a lot for the explanation. I wasn't aware there was a difference between single and double quotes, neither than they were creating a different class of array, I guess I do now !

Answer 2

[Ruger28]

why are you using

strcat

instead of

sprintf

Also, your data would be helpful, but try:

fprintf(sprintf("Les données des deux sessions de '%s' semblent venir de",...
    " deux distributions différentes.\n p = %4.3f \n", results_name{i}, pp));

[Carrillo Pablo]

Yeah sorry for the lack of context but thanks for the help, let's make it more simple :

a=1;
b=2;
fprintf(strcat("Lorem ipsum dolor sit amet, %i consectetur adipiscing",...
    "quis nostrud exercitation ullamco laboris %i\n"), a, b);

I want to display the string on the command window and that the code don't exceed my limit of 85 width. Using strcat seems a bit overkill just to have a linebreak...

I don't quite understand the specificities of fprintf but can't achieve that using

disp()

[Ruger28]

what do you wish to be size limited: the output string or your code in the script editor?

[Carrillo Pablo]

The code in the editor.

[Ruger28]

I don't believe there is a way to do that on non-comments, so the scroll bar is most likely your only option.