how to read specific columns from several data files stored in a folder.

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assuming we have a folder that has several data files inside it and the data files are in row/column format, how we can read or extract only specified columns of each file, process them as we need and then move to the next file and so on, rather than reading the whole files.
currently I am using the following code, but it reads the whole file, for effeciency purposes how I can modify this to make the table 't' consists of columns of my choice and not having to read the whole file? or is there a better way to do that?
filePattern = fullfile(myFolder, '*.*');
theFiles = dir(filePattern);
theFiles = theFiles(~[theFiles.isdir]); %remove folders from list
nfiles = length(theFiles);
fullnames = fullfile({theFiles.folder}, {theFiles.name});
results(:,1) = fullnames(:);
for k = 1 : nfiles
fullFileName = fullnames{k};
t = readtable(fullFileName);
end
  2 Comments
Stephen23
Stephen23 on 20 Sep 2021
"...how I can modify this to make the table 't' consists of columns of my choice and not having to read the whole file?"
Did you read the READTABLE documentation?
Or the documentation for READMATRIX or DLMREAD or any other function that you might use to import your file data?
MA
MA on 20 Sep 2021
thanks for the advice, I just checked the READTABLE documentation and sorted it out. thank you!

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