dumps coordinates of atomistic particles instead of coarse-grained particles in Adress simulation

  • dump() write configuration to trajectory GRO file. By default filename is “out.gro”, coordinates are folded.


  • filename Name of trajectory file. By default trajectory file name is “out.gro”

  • unfolded False if coordinates are folded, True if unfolded. By default - False

  • append True if new trajectory data is appended to existing trajectory file. By default - True

  • length_factor If length dimension in current system is nm, and unit is 0.23 nm, for example, then length_factor should be 0.23

  • length_unit It is length unit. Can be LJ, nm or A. By default - LJ

  • ftpl fixedtuplelist for the adres system


>>> ftpl = espressopp.FixedTupleListAdress(
>>> ftpl.addTuples(tuples)

writing down trajectory

>>> dump_conf_gro =, ftpl, integrator, filename='trajectory.gro')
>>> for i in range (200):
>>>   dump_conf_gro.dump()

writing down trajectory using ExtAnalyze extension

>>> dump_conf_gro =, ftpl, integrator, filename='trajectory.gro')
>>> ext_analyze = espressopp.integrator.ExtAnalyze(dump_conf_gro, 10)
>>> integrator.addExtension(ext_analyze)

Both exapmles will give the same result: 200 configurations in trajectory .gro file.

setting up length scale

For example, the Lennard-Jones model for liquid argon with \(\sigma=0.34 [nm]\)

>>> dump_conf_gro =, ftpl, integrator, filename='trj.gro', unfolded=False, length_factor=0.34, length_unit='nm', append=True)

will produce trj.gro with in nanometers, fixedtuplelist, integrator, filename, unfolded, length_factor, length_unit, append)
  • system
  • fixedtuplelist
  • integrator
  • filename – (default: ‘out.gro’)
  • unfolded – (default: False)
  • length_factor (real) – (default: 1.0)
  • length_unit – (default: ‘LJ’)
  • append – (default: True)
Return type: