show read_file function, everything else is just blind guessing. Several lines from the beginning of the file (incl. header, if there is one) would be helpful too. You can provide dummy data, but the structure should be the same as the real file
If you can't explain it to a six year old, you don't understand it yourself, Albert Einstein
How to Ask Questions The Smart Way: link and another link
Create MCV example
Debug small programs
How to Ask Questions The Smart Way: link and another link
Create MCV example
Debug small programs