count the # of rows of CSV files in a folder, part 2

https://www.mathworks.com/matlabcentral/answers/1748155-count-the-of-rows-of-csv-files-in-a-folder?s_tid=srchtitle discussed how to count the total # of rows from CSV files in a folder. Now I want to consider a situation that there are subfolders in the folder that contains CSV files and I want to count the total # of rows from CSV files in all subfolders.

From https://www.mathworks.com/matlabcentral/answers/437494-how-to-loop-through-all-files-in-subfolders-in-a-main-folder, I can think of

D = 'full path to the main folder';
S = dir(fullfile(D,'*'));
N = setdiff({S([S.isdir]).name},{'.','..'}); % list of subfolders of D.
numRowsTotal = 0;
for ii = 1:numel(N)
    T = dir(fullfile(D,N{ii},'*')); % improve by specifying the file extension.
    C = {T(~[T.isdir]).name}; % files in subfolder.
    for jj = 1:numel(C)
        F = fullfile(D,N{ii},C{jj})
        % do whatever with file F.
        datatable = readtable(F, 'ReadVariableNames', false);  %or true if there is a header
        numRowsTotal = numRowsTotal + height(datatable);
    end
end

Will this work?

Answer 1

[Image Analyst]

Maybe, but that's unnecessarily complicated. Just use ** in dir to get only csv files in the top level folder and subfolders and don't worry about isdir and set diff and two loops

folder = pwd;
fileList = dir(fullfile(folder,'**\*.csv'));
totalNumberOfLines = 0;
for k = 1 : numel(fileList)
	fullFileName = fullfile(fileList(k).folder, fileList(k).name);
	t = readtable(fullFileName);
	theseLines = height(t);
	totalNumberOfLines = totalNumberOfLines + theseLines;
	fprintf('%s has %d rows.\n', fullFileName, theseLines)
end
fprintf('In %d CSV files there are %d lines total.\n', numel(fileList), totalNumberOfLines)

[alpedhuez]

Thank you.