How to define a vector for multiple files

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I have a series of .txt tiles that all contain 3 columns; depth, temperature and salinity. I want to create a vector for depth, temperature and salinity for all of these files without individually writing out the names of each as there is a lot.
I tried to use the following script to accomplish this but get the error message 'index exceeds Matrix Dimensions'. Any help would be greatly appreciated.
files=dir('*.txt');
for i=1:length(files)
eval(['load ' files(i).name ' -ascii']);
end
Depth(:,1)=files(:,1);
Temp(:,1)=files(:,2);
Sal(:,1)=files(:,3);
  1 Comment
Jos (10584)
Jos (10584) on 19 Feb 2014
files is a variable holding the names of the text files, not the contents of it. This is causing the error message.

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Accepted Answer

Jos (10584)
Jos (10584) on 19 Feb 2014
Do not use eval!
files=dir('*.txt');
for i=1:length(files)
tempdata = load(files(i).name, '-ascii')
% now tempdata *only* holds the values from the last file.
% You want to store them for use, outside the for-loop.
% A convenient way is to use structures:
data(i).depth = tempdata(:,1) ;
data(i).temp = tempdata(:,2) ;
data(i).sal = tempdata(:,3)
end
Now, for instance,
allsal = cat(1,data(:).sal)
will give you all the salinity values of all files concatenated into a single vector
  3 Comments
Tom Wetherill
Tom Wetherill on 19 Feb 2014
It works but only for the last file in the directory. If i plot(data(i).temp,data(i).depth) it only plots a figure for the last file. Is there a way to plot a figure for each file at once?
Anthony
Anthony on 19 Feb 2014
At the end of the loop, i==length(files). If you want to plot the data of a all files, do:
for k=1:length(files)
figure(k)
plot(data(k).temp,data(k).depth); %kth file
end

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