MATLAB: Assign variables while importing data

assign variabledata import

I have a data set with multiples files, and there are 2 coloumns in each file. I have imported the files using the following code:
  files = dir('*.txt');
for i=1:length(files)
    eval(['load ' files(i).name ' -ascii']);
    
end
I have the data in my workspace now but I need to assign variables to each coloumn. Furthermore, I have to use those variables in a function to normalize all the data at the same time and plot in a single graph.
Is there any approach I can take to assign variables so that the code goes through each file one by one, and take the assigned variables to give answer for all dataset at once. 
function [zero,norm,ramanzeronorm] = zeronorm(wavenumber,rm)
My variables are wavenumber and rm.
Any help will be appreciated.

Best Answer

Do NOT use eval for importing data, unless you intentionally want to force yourself into writing slow, complex, buggy code. Read this to know why:
https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval
Instead you should import the data into a matrix, optionally assigning it to one array using indexing, for example using a cell array as the documentation examples show:
https://www.mathworks.com/help/matlab/import_export/process-a-sequence-of-files.html
Or using the same structure returned by dir:
S = dir('*.txt');
for k = 1:numel(S)
    M = dlmread(S(k).name); % better than LOAD.
    ... do whatever with matrix M, e.g.:
        wn = M(:,1); % wavenumber
        rn = M(:,2); % rn
    ...
    S(k).data = M; % optional: store any data you want for later.
end
Then you can trivially access the data in that structure, e.g. using loops or indexing:
https://www.mathworks.com/help/matlab/matlab_prog/access-multiple-elements-of-a-nonscalar-struct-array.html
For example, you can easily vertically concatenate all of the file data together:
alldata = vertcat(S.data);
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