GROMACS

Dear GROMACS Development Team,

Hello everybody. I am doing analysis of helix properties using GMX helix command in Gromacs 2016.4 as well as in 2018.2. While running the command I have the following issue after executing the following command..

GROMACS: gmx helix, version 2016.4
Executable: /usr/bin/gmx
Data prefix: /usr
Working dir: /storage/home/local/bude-loc/Desktop/PS2/Seed1/TM1
Command line:
gmx helix -f ../md1.xtc -s ../md.tpr -n index.ndx

Reading file ../md.tpr, VERSION 2018.2 (single precision)
Reading frame 0 time 490000.000 Please select a group containing the entire backbone
Group 0 ( System) has 201382 elements
Group 1 ( Protein) has 22327 elements
Group 2 ( Protein-H) has 11159 elements
Group 3 ( C-alpha) has 1414 elements
Group 4 ( Backbone) has 4242 elements
Group 5 ( MainChain) has 5651 elements
Group 6 ( MainChain+Cb) has 6978 elements
Group 7 ( MainChain+H) has 6986 elements
Group 8 ( SideChain) has 15341 elements
Group 9 ( SideChain-H) has 5508 elements
Group 10 ( Prot-Masses) has 22327 elements
Group 11 ( non-Protein) has 179055 elements
Group 12 ( Other) has 179055 elements
Group 13 ( POPC) has 40468 elements
Group 14 ( TIP3) has 138315 elements
Group 15 ( SOD) has 146 elements
Group 16 ( CLA) has 126 elements
Group 17 ( a_10635-11031) has 397 elements
Select a group: 17
Selected 17: 'a_10635-11031'
Checking group a_10635-11031
There are 25 residues
There are 23 complete backbone residues (from 2 to 24)
nall=397
Reading file ../md.tpr, VERSION 2018.2 (single precision)
helix from: 8 through 23

The same problem also in case of 2018.2 . Though the other helix properties including gmx helixorient and gmx bundle works fine in both the versions...

I have attached the last ns trajectory with 10 snapshots for your kind perusal and necessary input.

Thanking You
With Warm regards
Budheswar