[gmx-users] cg and contraints error

Sampo Karkola Sampo.Karkola at helsinki.fi
Mon Mar 6 11:48:37 CET 2006


I was trying to do energy minimisation using cg after a succesful 
minimisation with steepest descent. I get fatal error from grompp 
complaining about constraints

creating statusfile for 1 node...

Back Off! I just backed up mdout.mdp to ./#mdout.mdp.4#
checking input for internal consistency...
calling /lib/cpp...
processing topology...
Generated 182 of the 1128 non-bonded parameter combinations
Excluding 3 bonded neighbours for Protein 1
Excluding 2 bonded neighbours for SOL 11316
Excluding 1 bonded neighbours for NA+ 40
Excluding 1 bonded neighbours for CL- 41
processing coordinates...
double-checking input for internal consistency...
ERROR: can not do Conjugate Gradients with constraints (33948)
Fatal error: There was 1 error

In my mdp file I have constraints = none and FLEX_SPC water included. In 
one of the mailing list answers there was a suggestion that the 
constraints are hardcoded to topology followed by a question if there 
any dummies in the topology. What does this hardcoding mean? I do not 
have any dummies in the topology.



Sampo Karkola, M.Sc.

Laboratory of Organic Chemistry
Department of Chemistry
Faculty of Science
PO Box 55 (A.I. Virtasen aukio 1)
FIN-00014 University of Helsinki

tel +358 9 19150369
fax +358 9 19150366

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