MATLAB Answers


error with changing directory in for loop

Asked by Vincent Davis on 16 Jul 2019
Latest activity Edited by Walter Roberson
on 16 Jul 2019
I'm having a problem with "cd" when looping through folders using an SSH (Putty). Here is the relevant part of my function:
for ii = 1:10
parfor i=1:size(xmat,1)
file = sprintf('res_%d',i);
x0 = xmat(i,:);
[t,Y] = hackathon_ode(x0);
myFolder = cd(['output/mat_npaths_1000/np_10000_binsz_0.01/' int2str(ii) '/']);
dlmwrite(file, [t Y], ' ')
x1 = xmat1(i,:);
[t,Y] = hackathon_ode(x1);
myFolder = cd(['output/mat_npaths_1000/np_10000_binsz_0.1/' int2str(ii) '/']);
dlmwrite(file, [t Y], ' ')
And I get this as an output:
cannot CD to
(Name is nonexistent or not a directory).
This is what it should look like:
When I run this from my computer it works fine. Can anyone see what I'm missing and why it repeats the directory on Putty?


Sign in to comment.

1 Answer

Answer by Adam Danz
on 16 Jul 2019
 Accepted Answer

Do not use cd(); use fullfile() instead and then feed in the full path of the file to dlmwrite().

  1 Comment

I agree with Adam Danz's suggestion. As an explanation for what's happening: you cd into a directory but then never return to the directory you were in before the cd call. Therefore when you cd a second time, you're changing to a directory relative to where you were after your first cd.
Or to use a whimsical example: you're doing the Hokey Pokey by putting your right foot in then trying to put your right foot in again. You skipped the "put your right foot out" step inbetween.

Sign in to comment.