[gmx-users] Not enough ref_t and tau_t values

[Ashutosh Jogalekar]

I know this question has been discussed a number of times on the  
list, but almost everytime it has been discussed in reference to the  
index file.
I am getting this error during grompp for the position restrained MD  
even though I am not using any index file. The only groups I have are  
solvent and protein and accordingly, there are two columns for these  
two in the tau_t and ref_t fields in the pr.mdp file:

tau_t=       0.1         0.1
tc_grps=   protein  sol
ref_t=        300       300

my command is:

grompp -f pr.mdp -c test_b4pr.gro -p test.top -o test_em.tpr

In spite of this, the error is showing up again and again. The top  
file also has a row only for protein and solvent.
Help would be gladly appreciated as I cannot think of any reason  
since all the files look ok.
Thanks very much
Ashutosh Jogalekar
Emory University