Matlab allow access to folder for mkdir

will help you I think it would be better to use fullfile command to construct the path names and sprintf to format the strings:

rootPath = fullfile( 'c:', 'Users', 'kanje', 'Desktop' );
for ai=1:10
    baseName = fullfile( rootPath, sprintf( 'a%02d_e01', ai ) );
    mkdir( baseName );
    for sub = {'convolution', 'unconvolution' }
        mkdir( fullfile( baseName, sub{1} ) );
        for si=1:10
            subName = fullfile( baseName, sub{1}, sprintf( 'a%02d_s%02d_e01', ai, si ) );
            mkdir( subName );
        end
    end
end

This might help you Since you are using rmdir without the /S switch I assume the folder of interest is empty, so why removing and recreating it? You could simply create it and suppress the error message in case it already exists, like:

mkdir "folder" 2> nul

rmdir "folder" 2> nul & mkdir "folder"

rmdir /S /Q "folder" & mkdir "folder"

will be helpful for those in need Hope this code will be helpful to you.
At first go might this solutions seems inefficient but it will work for sure without having database involvement.

<?php
ini_set('display_errors', 1);
$counter=1;
$path="/path/to/folder/test";
while(is_dir($path))
{
    $path="/path/to/folder/{$counter}test";
    $counter++;
}
mkdir($path);

may help you . I have only one answer for you: don't waste your energy getting 100% code coverage. There are plenty of situations where it's not worth the effort and thus a waste of time and money. Moreover, convoluted tests to cover hard-to-test things like private constructors, exceptions from utility classes or direct interactions with the system (file, network etc) are hard to understand and maintain. They only add technical debt to your application without adding any value at all.
Don't write separate unit tests for anemic model classes either (i.e. POJO's with only fields, getters and setters and no logic). These classes should be used elsewhere and covered as part of other tests.

help you fix your problem I am trying to read an excel file which is a sub-folder of my current Matlab folder. I am using the code below for that: , The string

'\Reference data\Aircraft OOP.xlsx'

'Reference data\Aircraft OOP.xlsx'