[gmx-users] What 's the format of tabble for dihedral potential ?

[肖强]

Dear all, 
     In MD silulation, usually we use the  default function type for the dihedral potential. For example, type 3 means the Ryckaert-Bellemans function. However, sometimes we meet with some strange dihedrals that cannot be fitted by these functions, in this way we choose the tabulate potential with a tabble inside which the tabulate potentials and force were written. 
      In my work, I use a tabble (table_d0.xvg ) for a dihedral potential, but it cannot work. I hope someone can help me find out the reason. In my tabble, three columns are listed representing the dihedral angle (range from -180 to 180), the correspond potential and force. The first four lines of my table are listed here:
 -180.0000       29.4710     0.0000
 -179.0000       29.4061     0.0000
 -178.0000       29.4061     0.0000
 -177.0000       29.5288     0.0000   ... ...
But when running the MD, it cause a fatal error: The angles in file table_d0.xvg should go from -180.000000 to 180.000000 instead of -180.000000 to 0.000000! I am vary sure that my table was listed from -180 to 180, so I am confused. I wondder wether the format of my tabble is wrong and I wish somebody can help me out of this problem. Thanks for any add, sincerely!