I have 200 files with 20 columns each. The 1st column remains the same for all files. I want to sum up all 2nd columns from 200 files, .....20th columns from 200 files. I want the first column to remain the same.

file 1:

1 2 3 4

2 2 3 2

file 2:

1 3 4 1

2 1 3 2

output should be:

1 5 7 5

2 3 6 4

Answer 1

[StefBu]

Hi you have to use a for-loop to access your data and then add up the colums.

First use dir to get your files

files = dir('C:\users\...');

then create your output

Output = [];

then loop through your data, import them (that of course depends on the type of data):

Be sure to use double as datatype or it wont run.

for iFile = 1:size(files,1)
    tempFile = importdata(fullfile(files(iFile).folder, files(iFile).name)); % get data 
    
    if iFile = 1
        Output = tempFile; % write data for first run through the loop
    else
        tempFile(:,1) = 0; % make first column zeros so it doesnt change on adding up
        Output = Output + tempFile; % add up data
    end
    
end