How can I use fprintf to save a txt file with different size matrix ?

Hi,

I am using the following and works fine :

    saveAs = [fPath '\' fPrefix fmid '_' trialNo{4} '_FVL.txt']; 
    fid = fopen(saveAs, 'w');
    fprintf(fid, '%s\t %s\t %s\n', 'Time [s]', 'FL [mm]','EMG [v]');
    for v = 1: ufsize ; 
    fprintf(fid, '%d\t %d\t %d\n', Ultratimefinal0(v), lfascicle(v), EMG(v) );
    end
    fclose(fid);

The problem is when I am trying to cut some values from EMG ex. EMGc = EMG(16:end); then I am getting the "Index exceeds matrix dimensions" error. How can I save these different sized values ? I would like to have something like this:

    1 1
    1 1
    1 1
    1 1
    1
    1
    1
    1
And something else... how can I move the whole matrix in a specific row ? 

    1 
    1 
    1 1
    1 1
    1 1
    1 1
    1
    1

Thanks a lot.

Answer 1

[Christopher Berry]

One way you might do this is to use if-else statements around your fprintf, like this:

 fprintf(fid, '%d\t', Ultratimefinal0(v));

 if ( v < numel(lfascicle) )
     fprintf(fid, '%d\t', lfascicle(v));
 else
     fprintf(fid, '\t');
 end

 if ( v < numel(EMG) )
     fprintf(fid, '%d\n', EMG(v));
 else
     fprintf(fid, '\n');
 end

This will accomplish the first case you showed... As for the second case, you could shift your whole column by using an offset in the EMG part like this:

 offset = 2; % Just like your example, but this could be anything

 if ( v>offset && ( v-offset) < numel(EMG) )
     fprintf(fid, '%d\n', EMG(v-offset));
 else
     fprintf(fid, '\n');
 end

[Aris]

Thanks Christopher, your answer was really helpful.

Answer 2

[Robert Cumming]

you can loop over the column dimension of your variables when you write the file out, or before the write command check that each of your variables exist - if not customise the fprintf command.

You might also be interested in the function fullfile.