[gmx-users] CgenFF conversion failed

[Albert]

Hello,

I generated a ligand.str file from Parachem website. Then, I try to 
convert it to Gromacs format with command line:

 >cgenff_charmm2gmx.py UNK ligand.mol2 ligand.str charmm36-jul2017.ff


However, the job always failed with the following messages:

NOTE1: Code tested with python 2.7.3. Your version: 2.7.12 (default, Jul 
01 2016, 15:36:53) [GCC]

NOTE2: Please be sure to use the same version of CGenFF in your 
simulations that was used during parameter generation:
--Version of CGenFF detected in  ligand.str : 4.0
--Version of CGenFF detected in charmm36-jul2017.ff/forcefield.doc : 4.0

NOTE3: In order to avoid duplicated parameters, do NOT select the 
'Include parameters that are already in CGenFF' option when uploading a 
molecule into CGenFF.
Traceback (most recent call last):
   File "/home/albert/bin/cgenff_charmm2gmx.py", line 799, in <module>
     m.read_charmm_rtp(rtplines,atomtypes)
   File "/home/albert/bin/cgenff_charmm2gmx.py", line 540, in 
read_charmm_rtp
     self.G.add_node(self.natoms, atm[self.natoms])
TypeError: add_node() takes exactly 2 arguments (3 given)


I didn't select the 'Include parameters that are already in CGenFF' 
option when uploading a molecule into CGenFF.


Does anybody have any idea how to solve this problem?

Thanks a lot

Albert