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Writing a text file with information from a data file

Asked by Jonathan on 25 Jun 2012

Hi, I need to be able to take a .dat file that contains 5 strings of the filenames of .jpg images, and out put a .txt file that contains the name of each string and other data for EACH string (i.e. each .jpg image). I figured out how to generate this for one of the strings, but I don't know how to do it for all of the strings. Maybe use some sort of loop?

 fileID = fopen('nameOfFile.dat');
 filename = fgets(fileID)
 fileID2 = fopen('nameOfFile.txt','wt');
 info = 'blah blah';
 num = 5;
 fprintf(fileID2,'Filename: %s\n Info: %s\n Number:  %g\n',filename,info,num);
 fclose(fileID);
 fclose(fid);    

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UPDATE: I have figured out how to generate this for all of the strings, but I can only do it if I know how many strings there are. I need to be able to do it with any input data file (not just one with 5 strings). Also, I need the info and num to be able to be different for each filename.

fileID = fopen('nameOfFile.txt','wt');
filename = textread('nameOfFile.dat','%s\n')  
info = 'blah blah blah';
num = 5;
fprintf(fileID,'Filename: %s\nInfo: %s\nNumber: %g\n',filename{1},info,num,filename{2},info,num,filename{3},info,num,filename{4},info,num,filename{5},info,num);
fclose(fileID);

1 Comment

Jonathan on 25 Jun 2012

I figured it out! It was much simpler than I thought.

fileID = fopen('nameOfFile.txt','wt');

filename = textread('nameOfFile.dat','%s\n');
for i = 1:length(filename)
info = 'blah blah blah';
num(i) = 5;
fprintf(fileID,'Filename: %s\nInfo: %s\nNumber: %g\n\n',filename{i},info,num(i));
end

fclose(fileID);

Jonathan

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1 Answer

Answer by per isakson on 25 Jun 2012
Accepted answer

This is a hint!

 % or a more specific wildcard pattern
 sad = dir( fullfile( folder_spec, '*.dat' ) );  
 file_name_list = permute( { sad.name }, [2,1] );  %  row vector
 fileID = fopen('nameOfFile.txt','wt');
 for file_name = file_name_list   % loop over all files
      image_file_name = textread( fullfile(folder_spec,file_name{:}, ... );
      info = something
      num = something else
      fprintf( fileID, 'Filename: %s\nInfo: %s\nNumber: %g\n'  ...
                       , image_file_name, info, num )
  end
  fclose( fileID );

2 Comments

Jonathan on 25 Jun 2012

Sorry, but this doesn't help me very much. I'm still confused.

per isakson on 25 Jun 2012

Cannot help without better description of the problem

per isakson

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