Variable in a string name

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Andrew 2014-9-23

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评论： Andrew 2014-9-23

I am reading columns of binary files to plot. I have all my files in one folder and I want to plot them and pull out certain data. How can I set up a loop that will go through all the files?

My idea so far:

1) Use D= dir('W:\Folder')

to retrieve the names of all the files

2) for i= 1:70

str = ('W:\Folder\D(i)\Data')

fid = fopen(str);

How can I insert the different names in the array D from step 1?

I tried sprintf but I believe there is a problem because it's a path.

Thank you for your help

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Answer 1

Geoff Hayes 2014-9-23

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Andrew - try using fullfile instead

 foldername = 'W:\folder';
 files      = dir(foldername);
 for k=1:length(files)
    % ignore directories
    if ~files(k).isdir
         % build the file name
         filename = fullfile(foldername,files(k).name);
         % open the file
         fid = fopen(filename);
         if fid>0
             % do stuff with file contents
             % close the file
             fclose(fid);
         end
    end
 end

You can use sprintf as well (something like str = sprintf('W:\folder\%s\,files(k).name)' but the above should work just as well.

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Image Analyst 2014-9-23

Very robust. But after looking at his question again, I think he want to use dir() to get directories rather than files . Why do I think that? Because D(i) is in the middle of "W:\Folder\D(i)\Data" so he intends D(i) to be a folder name. So I think he wants all the subfolders of "Folder" and Data are files inside the subfolders, and unfortunately Data may not have any extension to the filename. SO maybe "if ~files(k).isdir" should actually be "if files(k).isdir"

Andrew 2014-9-23