Use parfor and getting "Index exceeds matrix dimensions" error

Pleas need help , I use Parfor to run the code in parallel but I got "Index exceeds matrix diamensions"

when I run the code with for it runs normally.

Rootpath=('............');

flist1=dir(fullfile(Rootpath));
parfor i=3: size (flist1,1)

       inputpath=strcat(Rootpath,'/',flist1(i).name,'/');
   outpath=strcat('./Output/',flist1(i).name,'/');
   if ~isdir(outpath)
      mkdir(outpath);
   end
      Read_main(inputpath,outpath)

end

[Walter Roberson]

Which line is the error report on?

I recommend by the way that you use fullfile to create the path names

[NOOR AL-SHAKARJI]

on parfor line

Answer 1

[Walter Roberson]

You could end up with mysterious path problems in the case that your Rootpath was a global variable. Global variables are not copied to parfor workers.

[NOOR AL-SHAKARJI]

how can I tackle that?

[Walter Roberson]

If it is a global variable, copy it to a local variable and use that in the code.

Alternately, you can use parfevalOnAll() before running the parfor, running a small bit of code that creates Rootpath as a global variable and initializing it with the appropriate value.

Or since you do not appear to write to the variable in the code, you could use parallel.pool.constant()

But really, for a simple variable such as this, best would just be to avoid using a global variable.

[NOOR AL-SHAKARJI]

Thank You Alot!!!

Now it works

I just put the globla variable inside the body of parfor