How to adjust and save a .txt file within a for loop?

I have a .dpj file which is in fact a normal .txt file. I would like to open, change a number, save under a specific name and close the file all within a for loop without loosing the basic file.

My question is how I can do this for example if the number is standing in the line 100 of the text file behind KLEFF?

The filename under which I want to save the .dpj file should be numbered depending on the for loop.

By myself this part works except that the .dpj files are not readable anymore:

N=10;
for i=0:N;
  baseline_name='textfile';
  filename=[baseline_name,'_',num2str(i)];
  savename=strcat(char(filename),'.dpj');
  save (savename);
end

Many thanks in advance!

[Rik]

Aren't you saving an empty file with this command?

Answer 1

[Jan]

Folder = cd;  % Set accordingly
N = 10; 
for iFile = 0:N
  % Read the text:
  File = fullfile(Folder, sprintf('textfile%d.dpj', iFile));
  Str  = fileread(File);
  CStr = strsplit(Str, '\n');

    % Change the line:
    Line = CStr{100};
    Line = [strtok(Line, '='), sprintf('= %g', rand)];
    CStr{100} = Line;

    % Write the text:
    NewFile = fullfile(Folder, sprintf('textfile%d_modified.dpj', iFile));
    fid = fopen(NewFile, 'w');
    if fid == -1
      error('Cannot open file for writing: %s', FileName);
    end
    fprintf(fid, '%s\n', CStr{:});
    fclose(fid);
  end

Answer 2

[Nagi Aly]

Hello? I have a dataset in folder names 'train'. In train we have some folders (set00, .... set05), in each set we have some videos like V000, VOO1 ... and in each video we have some text files which contains data. I would like to go in and save all the columns 4 in eatch file into another fileText.I try with this code but I can not save the contents of the files in another file. If you can help me please

[Jan]

Please open a new thread for a new question. Then post your code and explain what this means: "I can not save the contents of the files in another file".