[gmx-users] g_angle periodic

[ayşe K]

Dear Users,
I compute dihedral angles using g_angle. I want to print dihedral angles 360 degrees with the option periodic. For this purpose I used comment below;
g_angle -f traj.xtc -n angle.ndx -type dihedral -od dihedral.xvg -periodic
but  dihedrals vary in the range of -180 to 180. 
How can I calculate dihedral angles from 0 to 360 degrees?
Thanks in advance,
Ayse.