Extracting a portion of a text document

[alarcon032002]

Thank you ichabod801 and Larz60+ for taking the time to answer me. The genome does not have a /n to indicate the end of the line. The genome can be found here https://www.ncbi.nlm.nih.gov/nuccore/NC_...port=fasta. What I did is o copy only the genomic sequence into a notepad and gave it a name. The text file I used to run the code is here http://s000.tinyupload.com/?file_id=1106...4885590464
I hope is not an easy fix and thanks again for helping me.