[gmx-users] noe restraints and g_disre problems

[N-J.M. Macaluso]

Hello,

I am trying to include NOE distance constraints in an MD simulation. It 
appears to be straightforward based on the manual's directions, but I'm 
having trouble with the analysis using g_disre (thus I don't know if the 
restraints were properly implemented). I have included constraints in the 
topology file as specified in the manual like this:

[ distance_restraints ]
; ai aj type index type' low up1 up2 fac
  14  8  1    0      1    0.0  .15  .28  1.0
  14  9  1    0      1    0.0  .28  .35  1.0

15 other restraints follow these. I treat all of them simulataneously 
(indexes are 0), and I have assigned small noe signals a range of .15 - .28 
nm, medium .28 - 3.5, and large .35 - .50. In addition, I have included the 
following commands in the .mdp file: disre = No disre-weighting = Equal 
disre_mixed = no disre-fc = 1000 disre-tau = 0 nstdisreout = 100

After I ran the simulation, I tried using the program g_disre and received 
empty output from the program. When g_disre completes its run it states 
"There are 0 restraints and 0 pairs."

Is this a problem with g_disre or are the constraints not implemented 
properly? How can I tell if the constraints were included in the 
simulation?

Many thanks,

Max