[ESPResSo-users] Checkpoint load bug?

[Martin Kaiser]

Hi everybody!

I wanted to start  using the checkpointing function in Espresso 4.0 and followed closely the documentation.

I can checkpoint everything without an error, registering quantities with 

checkpoint.register("system.non_bonded_inter")

checkpoint.register("system.bonded_inter")

checkpoint.register("system.thermostat")

checkpoint.register("system.part")

commands and saving everything in my integration loop with the checkpoint.save( ) command works fine.

But upon calling the checkpoint-file with checkpoint.load( ), I get the following error:

Traceback (most recent call last):

  File "newcubes.py", line 135, in <module>

    checkpoint.load()

  File "/home/lv70488/a1306705/espresso-4-0/build/src/python/espressomd/checkpointing.py", line 232, in load

    checkpoint_data = pickle.load(f)

  File "particle_data.pyx", line 1819, in espressomd.particle_data.ParticleList.__setstate__

  File "particle_data.pyx", line 1918, in espressomd.particle_data.ParticleList._place_new_particle

  File "particle_data.pyx", line 1593, in espressomd.particle_data.ParticleHandle.update

  File "particle_data.pyx", line 1149, in espressomd.particle_data.ParticleHandle.exclusions.__set__

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

Now as far as I know, this is an error-message produced by numpy if one wants to check  the truth value of an array.

Is this a bug in the code or did I not pass an argument correctly?

Thanks for the help!

Martin