Merging text files according to time

Hi,

I am using the following code to merge data from several text files in the directory into a single file

files=dir('*.txt');

fileout='merged.txt';

fout=fopen(fileout,'w');

for cntfiles=1:length(files)

fin=fopen(files(cntfiles).name);

while ~feof(fin)

fprintf(fout,'%s %d\n',fgetl(fin),cntfiles);

end

fclose(fin);

end

fclose(fout);

How do i megre text files according to the time it was created. For instance i have 4 files in a directory and in the merged texted file the first data should be from the 1st file created, the second is the second file created and so on....

Answer 1

[Astik Sachan]

Hi Shreenath,

What you want is to sort the files (variable) on the basis of Time

Here is the code to do that

files   = dir('*.txt')
files   = struct2cell(files)
files   = files'            % to transpose the cell created
[S , I] = sort(files(:,3)); % make sure if '3' is your Time Field 
files   = files(I,:)        % sorted variable files

Enjoy your day!

Thanks

[Stephen23]

The field order returned by dir is not guaranteed, which makes this line very fragile:

files = struct2cell(files)

In fact, this line would likely cause a bug between versions that include the folder field and those without. Better, much more robust code would simply refer to the required field itself.

[Shreenath Krishnamurthy]

Hi, I am having a couple of issues

1. When i try Astiks code, in a directory containing 7000 files, the files are not sorted properly according to date if there are files from two months i.e 31 may and 1, 2june.
2. I get files which contains the names of the files directory date created etc. How do i use this information now to write to a single text file. i.e how do i use 'files' in fopen to read all these files.

thanks for your help.

[Astik Sachan]

Try This then

files   = dir('*.txt')
files   = struct2table(files)
[S , I] = sort(files.datenum);
files   = files(I,:)   

This is based on Datenum that is a timestamp in Numeric Form.