Source code for espressomd.io.mpiio

# Copyright (C) 2010-2018 The ESPResSo project
#
# This file is part of ESPResSo.
#
# ESPResSo is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# ESPResSo is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
from ..script_interface import PScriptInterface


[docs]class Mpiio: """MPI-IO object. Used to output particle data using MPI-IO to binary files. .. note:: See the write and read methods for documentation. """ def __init__(self): self._instance = PScriptInterface( "ScriptInterface::MPIIO::MPIIOScript")
[docs] def write(self, prefix=None, positions=False, velocities=False, types=False, bonds=False): """MPI-IO write. Outputs binary data using MPI-IO to several files starting with prefix. Suffixes are: - head: Information about fields that are dumped, - pref: Information about processes: 1 int per process, - id: Particle ids: 1 int per particle, - pos: Position information (if dumped): 3 doubles per particle, - vel: Velocity information (if dumped): 3 doubles per particle, - typ: Type information (if dumped): 1 int per particle, - bond: Bond information (if dumped): variable amount of data, - boff: Bond offset information (if bonds are dumped): 1 int per particle. .. note:: Do not read the files on a machine with a different architecture! Parameters ---------- prefix : :obj:`str` Common prefix for the filenames. positions : :obj:`bool`, optional Indicates if positions should be dumped. velocities : :obj:`bool`, optional Indicates if velocities should be dumped. types : :obj:`bool`, optional Indicates if types should be dumped. bonds : :obj:`bool`, optional Indicates if bonds should be dumped. Raises ------ ValueError If no prefix was given or none of the output fields are chosen. """ if prefix is None: raise ValueError( "Need to supply output prefix via 'prefix' kwarg.") if not positions and not velocities and not types and not bonds: raise ValueError("No output fields chosen.") self._instance.call_method( "write", prefix=prefix, pos=positions, vel=velocities, typ=types, bond=bonds)
[docs] def read(self, prefix=None, positions=False, velocities=False, types=False, bonds=False): """MPI-IO read. This function reads data dumped by `write`. See the write documentation for details. .. note:: The files must be read on the same number of processes that wrote the data. The data must be read on a machine with the same architecture (otherwise, this might silently fail). """ if prefix is None: raise ValueError( "Need to supply output prefix via 'prefix' kwarg.") if not positions and not velocities and not types and not bonds: raise ValueError("No output fields chosen.") self._instance.call_method( "read", prefix=prefix, pos=positions, vel=velocities, typ=types, bond=bonds)
mpiio = Mpiio()