How can I iterate through all .txt files in a folder to process them with already written code?

I have raw mass spectral data in .txt files with m/z in one column and intensity in another column. Right now, I'm importing them individually using the textread function. I know the textread function is not suggested for use anymore, and I want to speed up my processing. Is there functions that would allow me to run through all of my data in a folder, typically one day's worth of data, and process it that way? I know it would probably include a for loop, but I'm unsure how to write it.

Answer 1

[Walter Roberson]

projectdir = 'location/of/text/files';

dinfo = dir(fullfile(projectdir, '*.txt'));
filenames = fullfile({dinfo.folder}, {dinfo.name});
numfiles = length(filenames);

for K = 1 : numfiles
    thisfile = filenames{K};
    thisdata = load(thisfile);
    mz = thisdata(:,1); intensity = thisdata(:,2);
    do something with mz and intensity
end

This assumes that the files are text files that have no headers (*) and are pure text in two columns separated by space or comma. load() of such a file will handle csv files for example.

If there are headers, then the easiest change is to switch from load() to readmatrix()

(*) Note: load() can handle headers in text file under the restricted situation that the header or comments have % as their first non-blank character on the line