Read different files with different names (string) in a loop in MATLAB

Hello All,

I have a folder with different .dat files in it (with different names such as a.dat, b.dat and...). I have created a cell with C={'a.dat', 'b.dat', 'c.dat', ...}. Now I want to read all of those files in a For loop. For example for the i=1 in the loop, I want to read the 'a.dat", for i=2, 'b.dat', and so on. Do you have any idea how can I do that? I am trying to use something similar to fid(i) = fopen(sprintf('C(1,i)'),'rt'); but it does not work.

Thanks

Answer 1

[Jacob Ward]

You don't need to use sprintf. Try the following:

 C={'a.dat', 'b.dat', 'c.dat',...};
 for i = 1:n
     fid(i) = fopen(C{i},'rt')
 end

[Guillaume]

Huh? That's a very roundabout way to access the content of a cell array

[Jacob Ward]

Wow, yeah I had a mind blank. Changed my answer to reflect my newfound common sense.

Answer 2

[Guillaume]

You use curly braces {} to access the content of a cell array. You don't use sprintf, or strjoin or any special function. Therefore:

for i = 1:n
   fid = fopen(C{i}, 'rt');
   %...
end

I would recommend using the full path to the files instead of relative paths.

folder = 'C:\somewhere\someplace';
filenames = {'a.dat', 'b.dat'};
for fileindex = 1:numel(filenames)
   fid = fopen(fullfile(folder, filenames{fileindex}), 'rt');
   %...
end

and use meaningful variable names as I've done above instead of C, i, etc.

Also, you could use dir to get the list of files instead of building it yourself.

Oh, and finally don't use 2d indexing (C{1, i}) on vectors when linear indexing (C{i}) is simpler and works regardless of the shape of the vector (column, row, along 3rd dimension, etc.)