Count Total Number of Rows for Multiple .txt files in a Folder

Hi, my question should be rather simple.

I have a folder over 2000 .txt files, each of which contains post processing data in the same format as each other. Each row is equivalent to 1 second. In order to know the total length of time, I would like to run some sort of loop to just count the total number of rows cumulatively for all files. A snippet of the file can be shown below.

I appreciate the help!

Answer 1

[Rik]

I don't think it is possible to avoid reading all files and count the number of lines in each (unless each line is a fixed length, in which case you can use the file size in bytes).

If your files are plain text you can use my readfile function, which you can get from the FEX. If you are using R2017a or later, you can also get it through the AddOn-manager. If you are using R2020b, you can also use the readlines function. You can use numel to count the number of lines. The last line might be empty, so you should probably check that.

[Craig Stevens]

I was trying to avoid that but I decided to just go with pulling each of them as you said, as you can see below. It certainly isn't efficient and took 12 minutes to run due to all the, but it worked for the one time I needed it. Thanks for the help.

folderName = 'C:\Users\xxxxxx';
fileInfo = dir([folderName filesep '*.txt']);
fileName={fileInfo.name}';
numberFiles = size(fileInfo(:,1));
numberFiles = numberFiles(1);
Length = zeros(1,numberFiles);

for k = 1:numberFiles;
    fullFileName = [folderName filesep fileName{k}];
    data = readtable(fullFileName);
    Length(k) = height(data); 
end
TotalLength = sum(Length);

[Rik]

numberFiles=numel(fileName) should do it in one go.

Also, if you just want to count the number of lines, you don't need to spend time parsing the data to a table.

I would also suggest using fullfile instead of this construction with filesep (fullfile will deal with trailing file separators in the folder name).