PyLammps breakdown when using atoms list

LAMMPS (11 Aug 2017)

I use PyLammps in iPython (jupyter notebook) in my Mac. The input is based on .in file in /examples/melt and translate it to PyLammps format according to manual. But when I input “L.atoms[0].position”, the iPython breakdown immediately. Different lists or objects, such on runs, system, fixes, computes, don’t occur the problem.

Pasted Graphic.tiff

LAMMPS (11 Aug 2017)

I use PyLammps in iPython (jupyter notebook) in my Mac. The input is based
on .in file in /examples/melt and translate it to PyLammps format according
to manual. But when I input “L.atoms[0].position”, the iPython breakdown
immediately. Different lists or objects, such on runs, system, fixes,
computes, don’t occur the problem.

​please update LAMMPS to the latest version (23 Oct 2017 currently) and try
again.

axel.​

Pasted Graphic.tiff (115 KB)

The LAMMPS version is updated (23 Oct 2017), but the same problem appeared again. The “atoms” list seems like make IPython (jupyter notebook) breakdown.
Details are listed below.

melt.html (257 KB)

Here is the output in log.lammps:

print "(x[1])" ERROR: Indexed per-atom vector in variable formula without atom map (../variable.cpp:4307) Last command: (x[1]

Atom maps are not created by default for atomic systems (no bonds).
You can force them to be created with the atom_modify map yes command
in your script (at the beginning).

Steve