Problem using fix wall/gran with zcylinder arg

Compiling from lammps-17Nov2016 tarball downloaded on 11Jan2017, I had a problem using an old script input with the new executable. The problem was in the fix wall/gran command, specifically with using the zcylinder argument. The error was in assigning the specified radius for the wall boundary.

Looking at fix_wall_gran.cpp, I noticed that line 152 was changed from older versions:

cylradius = force->numeric(FLERR,arg[iarg+1]);

compared to the new version

cylradius = force->numeric(FLERR,arg[iarg+3]);

The documentation still says that zycylinder requires just one argument after the keyword. I changed the 3 backed to 1, recompiled and the input script ran just fine. I don’t know if this will cause problems elsewhere but, to me, it looks like it should still be a 1.


from checking out the code and recent changes to it, i agree with your
change. This is a bug and your bugfix makes perfect sense. I will
include in a pending pull request so that it will be in the
next patch release of LAMMPS.

thanks for reporting and providing a bugfix.