text: user14187: I am trying to edit the "end" of my sequences in a GFF3 that contains 10000 sequences (so I do not want to do it manually). I want to add 30 residues to every single fragment. How can I do this?
  Currently, I have a file that looks like this:
  ##gff-version 3
  sp_P45452_MMP13_HUMAN   SignalP-5.0 signal_peptide  1   19  0.994300    .   .   .
  sp_Q8R2H5_PHLD_RAT      SignalP-5.0 signal_peptide  1   23  0.986089    .   .   .
  
  I would like to edit it so that it looks like this:
  ##gff-version 3
  sp_P45452_MMP13_HUMAN   SignalP-5.0 signal_peptide  1   49  0.994300    .   .   .
  sp_Q8R2H5_PHLD_RAT      SignalP-5.0 signal_peptide  1   53  0.986089    .   .   .
  
  Thank you!
  
  user298: That's what awk excels at! Simply set the input (-F '\t') and output (-v OFS='\t') record field separators to tab, and add 30 to the value of the fifth field on lines that don't start with a #:
  $ awk -F'\t' -v OFS='\t' '/^[^#]/{$5+=30}1' file.gtf 
  ##gff-version 3
  sp_P45452_MMP13_HUMAN   SignalP-5.0 signal_peptide  1   19  30.9943 .   .   .
  sp_Q8R2H5_PHLD_RAT  SignalP-5.0 signal_peptide  1   23  30.9861 .   .   .
  
  
original_text: 14187: <p>I am trying to edit the &quot;end&quot; of my sequences in a GFF3 that contains 10000 sequences (so I do not want to do it manually). I want to add 30 residues to every single fragment. How can I do this?</p>
  <p>Currently, I have a file that looks like this:</p>
  <pre><code>##gff-version 3
  sp_P45452_MMP13_HUMAN   SignalP-5.0 signal_peptide  1   19  0.994300    .   .   .
  sp_Q8R2H5_PHLD_RAT      SignalP-5.0 signal_peptide  1   23  0.986089    .   .   .
  </code></pre>
  <p>I would like to edit it so that it looks like this:</p>
  <pre><code>##gff-version 3
  sp_P45452_MMP13_HUMAN   SignalP-5.0 signal_peptide  1   49  0.994300    .   .   .
  sp_Q8R2H5_PHLD_RAT      SignalP-5.0 signal_peptide  1   53  0.986089    .   .   .
  </code></pre>
  <p>Thank you!</p>
   298: <p>That's what awk excels at! Simply set the input (<code>-F '\t'</code>) and output (<code>-v OFS='\t'</code>) record field separators to tab, and add 30 to the value of the fifth field on lines that don't start with a <code>#</code>:</p>
  <pre><code>$ awk -F'\t' -v OFS='\t' '/^[^#]/{$5+=30}1' file.gtf 
  ##gff-version 3
  sp_P45452_MMP13_HUMAN   SignalP-5.0 signal_peptide  1   19  30.9943 .   .   .
  sp_Q8R2H5_PHLD_RAT  SignalP-5.0 signal_peptide  1   23  30.9861 .   .   .
  </code></pre>
  