Problem with making a new directory

I created a code to save figures for each test for 5 subjects. It gives a warning that the subfolder already exists. So I tried to use if statements, and for the directory 'Data_examen1' it worked. But if I include making the subfolder also in my if-statement. It gives an error. I understand what's going wrong here... But I can't figure out how to get rid of the warning...

 for welke_pp=1:5 % for 5 subjects
...
for i_testen=1:5 % for 5 measurements
...
if ((i_testen == 1) && (welke_pp == 1))
mkdir Data_examen1 %make new directory
end
mkdir('Data_examen1', sprintf('pp%d', welke_pp)); %hmake a new subfolder. Here is the warning.
folder = 'Data_examen1';
subfolder = sprintf('pp%d',welke_pp);
pngFileName = sprintf('3Dplot_subject%d_trial%d.png', welke_pp, i_testen);
fullFileName = fullfile([folder '\\' subfolder], pngFileName);
saveas(gcf,fullFileName); %save each figure

Answer 1

[Image Analyst]

Just wrap your mkdir() in an if statement

if ~exist(folderName, 'dir')
    % Folder does not exist so create it.
    mkdir(foldername);
end

If it exists already, it won't do this and therefore won't throw an error.

[Sam]

For the subfolder, it is a bit harder I think... I tried this:

if ~exist(sprintf('pp%d', welke_pp), 'dir')
  mkdir(sprintf('pp%d', welke_pp))

But Matlab doesn't make the new subfolder...

[Image Analyst]

It should if you specify the full path of the folder.

subFolder = sprintf('pp%d', welke_pp);
fullPath = fullfile(someRootFolder, subFolder);
if ~exist(fullPath , 'dir')
    % Folder does not exist so create it.
    mkdir(fullPath );
end

Your code probably actually did create the folder but in a location you were not expecting and did not look for or in. Do it my way and look at the fullPath value and see if it makes sense. Then use the debugger to see if it actually enters the "if" block.

[Sam]

Thanks a lot! It works!