lammps/python/lammps.py

1082 lines
34 KiB
Python

# ----------------------------------------------------------------------
# LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
# http://lammps.sandia.gov, Sandia National Laboratories
# Steve Plimpton, sjplimp@sandia.gov
#
# Copyright (2003) Sandia Corporation. Under the terms of Contract
# DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
# certain rights in this software. This software is distributed under
# the GNU General Public License.
#
# See the README file in the top-level LAMMPS directory.
# -------------------------------------------------------------------------
# Python wrappers on LAMMPS library via ctypes
# for python3 compatibility
from __future__ import print_function
# imports for simple LAMMPS python wrapper module "lammps"
import sys,traceback,types
from ctypes import *
from os.path import dirname,abspath,join
from inspect import getsourcefile
# imports for advanced LAMMPS python wrapper modules "PyLammps" and "IPyLammps"
from collections import namedtuple
import os
import select
import re
import sys
def get_ctypes_int(size):
if size == 4:
return c_int32
elif size == 8:
return c_int64
return c_int
class MPIAbortException(Exception):
def __init__(self, message):
self.message = message
def __str__(self):
return repr(self.message)
class lammps(object):
# detect if Python is using version of mpi4py that can pass a communicator
has_mpi4py = False
try:
from mpi4py import MPI
from mpi4py import __version__ as mpi4py_version
if mpi4py_version.split('.')[0] in ['2','3']: has_mpi4py = True
except:
pass
# create instance of LAMMPS
def __init__(self,name="",cmdargs=None,ptr=None,comm=None):
self.comm = comm
self.opened = 0
# determine module location
modpath = dirname(abspath(getsourcefile(lambda:0)))
self.lib = None
# if a pointer to a LAMMPS object is handed in,
# all symbols should already be available
try:
if ptr: self.lib = CDLL("",RTLD_GLOBAL)
except:
self.lib = None
# load liblammps.so unless name is given
# if name = "g++", load liblammps_g++.so
# try loading the LAMMPS shared object from the location
# of lammps.py with an absolute path,
# so that LD_LIBRARY_PATH does not need to be set for regular install
# fall back to loading with a relative path,
# typically requires LD_LIBRARY_PATH to be set appropriately
if not self.lib:
try:
if not name: self.lib = CDLL(join(modpath,"liblammps.so"),RTLD_GLOBAL)
else: self.lib = CDLL(join(modpath,"liblammps_%s.so" % name),
RTLD_GLOBAL)
except:
if not name: self.lib = CDLL("liblammps.so",RTLD_GLOBAL)
else: self.lib = CDLL("liblammps_%s.so" % name,RTLD_GLOBAL)
# define ctypes API for each library method
# NOTE: should add one of these for each lib function
self.lib.lammps_extract_box.argtypes = \
[c_void_p,POINTER(c_double),POINTER(c_double),
POINTER(c_double),POINTER(c_double),POINTER(c_double),
POINTER(c_int),POINTER(c_int)]
self.lib.lammps_extract_box.restype = None
self.lib.lammps_reset_box.argtypes = \
[c_void_p,POINTER(c_double),POINTER(c_double),c_double,c_double,c_double]
self.lib.lammps_reset_box.restype = None
self.lib.lammps_gather_atoms.argtypes = \
[c_void_p,c_char_p,c_int,c_int,c_void_p]
self.lib.lammps_gather_atoms.restype = None
self.lib.lammps_gather_atoms_concat.argtypes = \
[c_void_p,c_char_p,c_int,c_int,c_void_p]
self.lib.lammps_gather_atoms_concat.restype = None
self.lib.lammps_gather_atoms_subset.argtypes = \
[c_void_p,c_char_p,c_int,c_int,c_int,POINTER(c_int),c_void_p]
self.lib.lammps_gather_atoms_subset.restype = None
self.lib.lammps_scatter_atoms.argtypes = \
[c_void_p,c_char_p,c_int,c_int,c_void_p]
self.lib.lammps_scatter_atoms.restype = None
self.lib.lammps_scatter_atoms_subset.argtypes = \
[c_void_p,c_char_p,c_int,c_int,c_int,POINTER(c_int),c_void_p]
self.lib.lammps_scatter_atoms_subset.restype = None
# if no ptr provided, create an instance of LAMMPS
# don't know how to pass an MPI communicator from PyPar
# but we can pass an MPI communicator from mpi4py v2.0.0 and later
# no_mpi call lets LAMMPS use MPI_COMM_WORLD
# cargs = array of C strings from args
# if ptr, then are embedding Python in LAMMPS input script
# ptr is the desired instance of LAMMPS
# just convert it to ctypes ptr and store in self.lmp
if not ptr:
# with mpi4py v2, can pass MPI communicator to LAMMPS
# need to adjust for type of MPI communicator object
# allow for int (like MPICH) or void* (like OpenMPI)
if comm:
if not lammps.has_mpi4py:
raise Exception('Python mpi4py version is not 2 or 3')
if lammps.MPI._sizeof(lammps.MPI.Comm) == sizeof(c_int):
MPI_Comm = c_int
else:
MPI_Comm = c_void_p
narg = 0
cargs = 0
if cmdargs:
cmdargs.insert(0,"lammps.py")
narg = len(cmdargs)
for i in range(narg):
if type(cmdargs[i]) is str:
cmdargs[i] = cmdargs[i].encode()
cargs = (c_char_p*narg)(*cmdargs)
self.lib.lammps_open.argtypes = [c_int, c_char_p*narg, \
MPI_Comm, c_void_p()]
else:
self.lib.lammps_open.argtypes = [c_int, c_int, \
MPI_Comm, c_void_p()]
self.lib.lammps_open.restype = None
self.opened = 1
self.lmp = c_void_p()
comm_ptr = lammps.MPI._addressof(comm)
comm_val = MPI_Comm.from_address(comm_ptr)
self.lib.lammps_open(narg,cargs,comm_val,byref(self.lmp))
else:
self.opened = 1
if cmdargs:
cmdargs.insert(0,"lammps.py")
narg = len(cmdargs)
for i in range(narg):
if type(cmdargs[i]) is str:
cmdargs[i] = cmdargs[i].encode()
cargs = (c_char_p*narg)(*cmdargs)
self.lmp = c_void_p()
self.lib.lammps_open_no_mpi(narg,cargs,byref(self.lmp))
else:
self.lmp = c_void_p()
self.lib.lammps_open_no_mpi(0,None,byref(self.lmp))
# could use just this if LAMMPS lib interface supported it
# self.lmp = self.lib.lammps_open_no_mpi(0,None)
else:
# magic to convert ptr to ctypes ptr
if sys.version_info >= (3, 0):
# Python 3 (uses PyCapsule API)
pythonapi.PyCapsule_GetPointer.restype = c_void_p
pythonapi.PyCapsule_GetPointer.argtypes = [py_object, c_char_p]
self.lmp = c_void_p(pythonapi.PyCapsule_GetPointer(ptr, None))
else:
# Python 2 (uses PyCObject API)
pythonapi.PyCObject_AsVoidPtr.restype = c_void_p
pythonapi.PyCObject_AsVoidPtr.argtypes = [py_object]
self.lmp = c_void_p(pythonapi.PyCObject_AsVoidPtr(ptr))
# optional numpy support (lazy loading)
self._numpy = None
# set default types
self.c_bigint = get_ctypes_int(self.extract_setting("bigint"))
self.c_tagint = get_ctypes_int(self.extract_setting("tagint"))
self.c_imageint = get_ctypes_int(self.extract_setting("imageint"))
# shut-down LAMMPS instance
def __del__(self):
if self.lmp and self.opened:
self.lib.lammps_close(self.lmp)
self.opened = 0
def close(self):
if self.opened: self.lib.lammps_close(self.lmp)
self.lmp = None
self.opened = 0
def version(self):
return self.lib.lammps_version(self.lmp)
def file(self,file):
if file: file = file.encode()
self.lib.lammps_file(self.lmp,file)
# send a single command
def command(self,cmd):
if cmd: cmd = cmd.encode()
self.lib.lammps_command(self.lmp,cmd)
if self.uses_exceptions and self.lib.lammps_has_error(self.lmp):
sb = create_string_buffer(100)
error_type = self.lib.lammps_get_last_error_message(self.lmp, sb, 100)
error_msg = sb.value.decode().strip()
if error_type == 2:
raise MPIAbortException(error_msg)
raise Exception(error_msg)
# send a list of commands
def commands_list(self,cmdlist):
cmds = [x.encode() for x in cmdlist if type(x) is str]
args = (c_char_p * len(cmdlist))(*cmds)
self.lib.lammps_commands_list(self.lmp,len(cmdlist),args)
# send a string of commands
def commands_string(self,multicmd):
if type(multicmd) is str: multicmd = multicmd.encode()
self.lib.lammps_commands_string(self.lmp,c_char_p(multicmd))
# extract lammps type byte sizes
def extract_setting(self, name):
if name: name = name.encode()
self.lib.lammps_extract_atom.restype = c_int
return int(self.lib.lammps_extract_setting(self.lmp,name))
# extract global info
def extract_global(self,name,type):
if name: name = name.encode()
if type == 0:
self.lib.lammps_extract_global.restype = POINTER(c_int)
elif type == 1:
self.lib.lammps_extract_global.restype = POINTER(c_double)
else: return None
ptr = self.lib.lammps_extract_global(self.lmp,name)
return ptr[0]
# extract global info
def extract_box(self):
boxlo = (3*c_double)()
boxhi = (3*c_double)()
xy = c_double()
yz = c_double()
xz = c_double()
periodicity = (3*c_int)()
box_change = c_int()
self.lib.lammps_extract_box(self.lmp,boxlo,boxhi,
byref(xy),byref(yz),byref(xz),
periodicity,byref(box_change))
boxlo = boxlo[:3]
boxhi = boxhi[:3]
xy = xy.value
yz = yz.value
xz = xz.value
periodicity = periodicity[:3]
box_change = box_change.value
return boxlo,boxhi,xy,yz,xz,periodicity,box_change
# extract per-atom info
# NOTE: need to insure are converting to/from correct Python type
# e.g. for Python list or NumPy or ctypes
def extract_atom(self,name,type):
if name: name = name.encode()
if type == 0:
self.lib.lammps_extract_atom.restype = POINTER(c_int)
elif type == 1:
self.lib.lammps_extract_atom.restype = POINTER(POINTER(c_int))
elif type == 2:
self.lib.lammps_extract_atom.restype = POINTER(c_double)
elif type == 3:
self.lib.lammps_extract_atom.restype = POINTER(POINTER(c_double))
else: return None
ptr = self.lib.lammps_extract_atom(self.lmp,name)
return ptr
@property
def numpy(self):
if not self._numpy:
import numpy as np
class LammpsNumpyWrapper:
def __init__(self, lmp):
self.lmp = lmp
def _ctype_to_numpy_int(self, ctype_int):
if ctype_int == c_int32:
return np.int32
elif ctype_int == c_int64:
return np.int64
return np.intc
def extract_atom_iarray(self, name, nelem, dim=1):
if name in ['id', 'molecule']:
c_int_type = self.lmp.c_tagint
elif name in ['image']:
c_int_type = self.lmp.c_imageint
else:
c_int_type = c_int
np_int_type = self._ctype_to_numpy_int(c_int_type)
if dim == 1:
tmp = self.lmp.extract_atom(name, 0)
ptr = cast(tmp, POINTER(c_int_type * nelem))
else:
tmp = self.lmp.extract_atom(name, 1)
ptr = cast(tmp[0], POINTER(c_int_type * nelem * dim))
a = np.frombuffer(ptr.contents, dtype=np_int_type)
a.shape = (nelem, dim)
return a
def extract_atom_darray(self, name, nelem, dim=1):
if dim == 1:
tmp = self.lmp.extract_atom(name, 2)
ptr = cast(tmp, POINTER(c_double * nelem))
else:
tmp = self.lmp.extract_atom(name, 3)
ptr = cast(tmp[0], POINTER(c_double * nelem * dim))
a = np.frombuffer(ptr.contents)
a.shape = (nelem, dim)
return a
self._numpy = LammpsNumpyWrapper(self)
return self._numpy
# extract compute info
def extract_compute(self,id,style,type):
if id: id = id.encode()
if type == 0:
if style > 0: return None
self.lib.lammps_extract_compute.restype = POINTER(c_double)
ptr = self.lib.lammps_extract_compute(self.lmp,id,style,type)
return ptr[0]
if type == 1:
self.lib.lammps_extract_compute.restype = POINTER(c_double)
ptr = self.lib.lammps_extract_compute(self.lmp,id,style,type)
return ptr
if type == 2:
self.lib.lammps_extract_compute.restype = POINTER(POINTER(c_double))
ptr = self.lib.lammps_extract_compute(self.lmp,id,style,type)
return ptr
return None
# extract fix info
# in case of global datum, free memory for 1 double via lammps_free()
# double was allocated by library interface function
def extract_fix(self,id,style,type,i=0,j=0):
if id: id = id.encode()
if style == 0:
self.lib.lammps_extract_fix.restype = POINTER(c_double)
ptr = self.lib.lammps_extract_fix(self.lmp,id,style,type,i,j)
result = ptr[0]
self.lib.lammps_free(ptr)
return result
elif (style == 1) or (style == 2):
if type == 1:
self.lib.lammps_extract_fix.restype = POINTER(c_double)
elif type == 2:
self.lib.lammps_extract_fix.restype = POINTER(POINTER(c_double))
else:
return None
ptr = self.lib.lammps_extract_fix(self.lmp,id,style,type,i,j)
return ptr
else:
return None
# extract variable info
# free memory for 1 double or 1 vector of doubles via lammps_free()
# for vector, must copy nlocal returned values to local c_double vector
# memory was allocated by library interface function
def extract_variable(self,name,group,type):
if name: name = name.encode()
if group: group = group.encode()
if type == 0:
self.lib.lammps_extract_variable.restype = POINTER(c_double)
ptr = self.lib.lammps_extract_variable(self.lmp,name,group)
result = ptr[0]
self.lib.lammps_free(ptr)
return result
if type == 1:
self.lib.lammps_extract_global.restype = POINTER(c_int)
nlocalptr = self.lib.lammps_extract_global(self.lmp,"nlocal".encode())
nlocal = nlocalptr[0]
result = (c_double*nlocal)()
self.lib.lammps_extract_variable.restype = POINTER(c_double)
ptr = self.lib.lammps_extract_variable(self.lmp,name,group)
for i in range(nlocal): result[i] = ptr[i]
self.lib.lammps_free(ptr)
return result
return None
# return current value of thermo keyword
def get_thermo(self,name):
if name: name = name.encode()
self.lib.lammps_get_thermo.restype = c_double
return self.lib.lammps_get_thermo(self.lmp,name)
# return total number of atoms in system
def get_natoms(self):
return self.lib.lammps_get_natoms(self.lmp)
# set variable value
# value is converted to string
# returns 0 for success, -1 if failed
def set_variable(self,name,value):
if name: name = name.encode()
if value: value = str(value).encode()
return self.lib.lammps_set_variable(self.lmp,name,value)
# reset simulation box size
def reset_box(self,boxlo,boxhi,xy,yz,xz):
cboxlo = (3*c_double)(*boxlo)
cboxhi = (3*c_double)(*boxhi)
self.lib.lammps_reset_box(self.lmp,cboxlo,cboxhi,xy,yz,xz)
# return vector of atom properties gathered across procs
# 3 variants to match src/library.cpp
# name = atom property recognized by LAMMPS in atom->extract()
# type = 0 for integer values, 1 for double values
# count = number of per-atom valus, 1 for type or charge, 3 for x or f
# returned data is a 1d vector - doc how it is ordered?
# NOTE: need to insure are converting to/from correct Python type
# e.g. for Python list or NumPy or ctypes
def gather_atoms(self,name,type,count):
if name: name = name.encode()
natoms = self.lib.lammps_get_natoms(self.lmp)
if type == 0:
data = ((count*natoms)*c_int)()
self.lib.lammps_gather_atoms(self.lmp,name,type,count,data)
elif type == 1:
data = ((count*natoms)*c_double)()
self.lib.lammps_gather_atoms(self.lmp,name,type,count,data)
else: return None
return data
def gather_atoms_concat(self,name,type,count):
if name: name = name.encode()
natoms = self.lib.lammps_get_natoms(self.lmp)
if type == 0:
data = ((count*natoms)*c_int)()
self.lib.lammps_gather_atoms_concat(self.lmp,name,type,count,data)
elif type == 1:
data = ((count*natoms)*c_double)()
self.lib.lammps_gather_atoms_concat(self.lmp,name,type,count,data)
else: return None
return data
def gather_atoms_subset(self,name,type,count,ndata,ids):
if name: name = name.encode()
if type == 0:
data = ((count*ndata)*c_int)()
self.lib.lammps_gather_atoms_subset(self.lmp,name,type,count,ndata,ids,data)
elif type == 1:
data = ((count*ndata)*c_double)()
self.lib.lammps_gather_atoms_subset(self.lmp,name,type,count,ndata,ids,data)
else: return None
return data
# scatter vector of atom properties across procs
# 2 variants to match src/library.cpp
# name = atom property recognized by LAMMPS in atom->extract()
# type = 0 for integer values, 1 for double values
# count = number of per-atom valus, 1 for type or charge, 3 for x or f
# assume data is of correct type and length, as created by gather_atoms()
# NOTE: need to insure are converting to/from correct Python type
# e.g. for Python list or NumPy or ctypes
def scatter_atoms(self,name,type,count,data):
if name: name = name.encode()
self.lib.lammps_scatter_atoms(self.lmp,name,type,count,data)
def scatter_atoms_subset(self,name,type,count,ndata,ids,data):
if name: name = name.encode()
self.lib.lammps_scatter_atoms_subset(self.lmp,name,type,count,ndata,ids,data)
# create N atoms on all procs
# N = global number of atoms
# id = ID of each atom (optional, can be None)
# type = type of each atom (1 to Ntypes) (required)
# x = coords of each atom as (N,3) array (required)
# v = velocity of each atom as (N,3) array (optional, can be None)
# NOTE: how could we insure are passing correct type to LAMMPS
# e.g. for Python list or NumPy, etc
# ditto for gather_atoms() above
def create_atoms(self,n,id,type,x,v,image=None,shrinkexceed=False):
if id:
id_lmp = (c_int * n)()
id_lmp[:] = id
else:
id_lmp = id
if image:
image_lmp = (c_int * n)()
image_lmp[:] = image
else:
image_lmp = image
type_lmp = (c_int * n)()
type_lmp[:] = type
self.lib.lammps_create_atoms(self.lmp,n,id_lmp,type_lmp,x,v,image_lmp,
shrinkexceed)
@property
def uses_exceptions(self):
""" Return whether the LAMMPS shared library was compiled with C++ exceptions handling enabled """
try:
if self.lib.lammps_has_error:
return True
except(AttributeError):
return False
# -------------------------------------------------------------------------
# -------------------------------------------------------------------------
# -------------------------------------------------------------------------
################################################################################
# Alternative Python Wrapper
# Written by Richard Berger <richard.berger@temple.edu>
################################################################################
class OutputCapture(object):
""" Utility class to capture LAMMPS library output """
def __init__(self):
self.stdout_pipe_read, self.stdout_pipe_write = os.pipe()
self.stdout_fd = 1
def __enter__(self):
self.stdout = os.dup(self.stdout_fd)
os.dup2(self.stdout_pipe_write, self.stdout_fd)
return self
def __exit__(self, type, value, tracebac):
os.dup2(self.stdout, self.stdout_fd)
os.close(self.stdout)
os.close(self.stdout_pipe_read)
os.close(self.stdout_pipe_write)
# check if we have more to read from the pipe
def more_data(self, pipe):
r, _, _ = select.select([pipe], [], [], 0)
return bool(r)
# read the whole pipe
def read_pipe(self, pipe):
out = ""
while self.more_data(pipe):
out += os.read(pipe, 1024).decode()
return out
@property
def output(self):
return self.read_pipe(self.stdout_pipe_read)
class Variable(object):
def __init__(self, lammps_wrapper_instance, name, style, definition):
self.wrapper = lammps_wrapper_instance
self.name = name
self.style = style
self.definition = definition.split()
@property
def value(self):
if self.style == 'atom':
return list(self.wrapper.lmp.extract_variable(self.name, "all", 1))
else:
value = self.wrapper.lmp_print('"${%s}"' % self.name).strip()
try:
return float(value)
except ValueError:
return value
class AtomList(object):
def __init__(self, lammps_wrapper_instance):
self.lmp = lammps_wrapper_instance
self.natoms = self.lmp.system.natoms
self.dimensions = self.lmp.system.dimensions
def __getitem__(self, index):
if self.dimensions == 2:
return Atom2D(self.lmp, index + 1)
return Atom(self.lmp, index + 1)
class Atom(object):
def __init__(self, lammps_wrapper_instance, index):
self.lmp = lammps_wrapper_instance
self.index = index
@property
def id(self):
return int(self.lmp.eval("id[%d]" % self.index))
@property
def type(self):
return int(self.lmp.eval("type[%d]" % self.index))
@property
def mol(self):
return self.lmp.eval("mol[%d]" % self.index)
@property
def mass(self):
return self.lmp.eval("mass[%d]" % self.index)
@property
def position(self):
return (self.lmp.eval("x[%d]" % self.index),
self.lmp.eval("y[%d]" % self.index),
self.lmp.eval("z[%d]" % self.index))
@position.setter
def position(self, value):
self.lmp.set("atom", self.index, "x", value[0])
self.lmp.set("atom", self.index, "y", value[1])
self.lmp.set("atom", self.index, "z", value[2])
@property
def velocity(self):
return (self.lmp.eval("vx[%d]" % self.index),
self.lmp.eval("vy[%d]" % self.index),
self.lmp.eval("vz[%d]" % self.index))
@property
def force(self):
return (self.lmp.eval("fx[%d]" % self.index),
self.lmp.eval("fy[%d]" % self.index),
self.lmp.eval("fz[%d]" % self.index))
@property
def charge(self):
return self.lmp.eval("q[%d]" % self.index)
class Atom2D(Atom):
def __init__(self, lammps_wrapper_instance, index):
super(Atom2D, self).__init__(lammps_wrapper_instance, index)
@property
def position(self):
return (self.lmp.eval("x[%d]" % self.index),
self.lmp.eval("y[%d]" % self.index))
@position.setter
def position(self, value):
self.lmp.set("atom", self.index, "x", value[0])
self.lmp.set("atom", self.index, "y", value[1])
@property
def velocity(self):
return (self.lmp.eval("vx[%d]" % self.index),
self.lmp.eval("vy[%d]" % self.index))
@property
def force(self):
return (self.lmp.eval("fx[%d]" % self.index),
self.lmp.eval("fy[%d]" % self.index))
class variable_set:
def __init__(self, name, variable_dict):
self._name = name
array_pattern = re.compile(r"(?P<arr>.+)\[(?P<index>[0-9]+)\]")
for key, value in variable_dict.items():
m = array_pattern.match(key)
if m:
g = m.groupdict()
varname = g['arr']
idx = int(g['index'])
if varname not in self.__dict__:
self.__dict__[varname] = {}
self.__dict__[varname][idx] = value
else:
self.__dict__[key] = value
def __str__(self):
return "{}({})".format(self._name, ','.join(["{}={}".format(k, self.__dict__[k]) for k in self.__dict__.keys() if not k.startswith('_')]))
def __repr__(self):
return self.__str__()
def get_thermo_data(output):
""" traverse output of runs and extract thermo data columns """
if isinstance(output, str):
lines = output.splitlines()
else:
lines = output
runs = []
columns = []
in_run = False
current_run = {}
for line in lines:
if line.startswith("Per MPI rank memory allocation"):
in_run = True
elif in_run and len(columns) == 0:
# first line after memory usage are column names
columns = line.split()
current_run = {}
for col in columns:
current_run[col] = []
elif line.startswith("Loop time of "):
in_run = False
columns = None
thermo_data = variable_set('ThermoData', current_run)
r = {'thermo' : thermo_data }
runs.append(namedtuple('Run', list(r.keys()))(*list(r.values())))
elif in_run and len(columns) > 0:
values = [float(x) for x in line.split()]
for i, col in enumerate(columns):
current_run[col].append(values[i])
return runs
class PyLammps(object):
"""
More Python-like wrapper for LAMMPS (e.g., for iPython)
See examples/ipython for usage
"""
def __init__(self,name="",cmdargs=None,ptr=None,comm=None):
if ptr:
if isinstance(ptr,PyLammps):
self.lmp = ptr.lmp
elif isinstance(ptr,lammps):
self.lmp = ptr
else:
self.lmp = lammps(name=name,cmdargs=cmdargs,ptr=ptr,comm=comm)
else:
self.lmp = lammps(name=name,cmdargs=cmdargs,ptr=None,comm=comm)
print("LAMMPS output is captured by PyLammps wrapper")
self._cmd_history = []
self.runs = []
def __del__(self):
if self.lmp: self.lmp.close()
self.lmp = None
def close(self):
if self.lmp: self.lmp.close()
self.lmp = None
def version(self):
return self.lmp.version()
def file(self,file):
self.lmp.file(file)
def write_script(self,filename):
""" Write LAMMPS script file containing all commands executed up until now """
with open(filename, "w") as f:
for cmd in self._cmd_history:
f.write("%s\n" % cmd)
def command(self,cmd):
self.lmp.command(cmd)
self._cmd_history.append(cmd)
def run(self, *args, **kwargs):
output = self.__getattr__('run')(*args, **kwargs)
self.runs += get_thermo_data(output)
return output
@property
def last_run(self):
if len(self.runs) > 0:
return self.runs[-1]
return None
@property
def atoms(self):
return AtomList(self)
@property
def system(self):
output = self.info("system")
d = self._parse_info_system(output)
return namedtuple('System', d.keys())(*d.values())
@property
def communication(self):
output = self.info("communication")
d = self._parse_info_communication(output)
return namedtuple('Communication', d.keys())(*d.values())
@property
def computes(self):
output = self.info("computes")
return self._parse_element_list(output)
@property
def dumps(self):
output = self.info("dumps")
return self._parse_element_list(output)
@property
def fixes(self):
output = self.info("fixes")
return self._parse_element_list(output)
@property
def groups(self):
output = self.info("groups")
return self._parse_groups(output)
@property
def variables(self):
output = self.info("variables")
vars = {}
for v in self._parse_element_list(output):
vars[v['name']] = Variable(self, v['name'], v['style'], v['def'])
return vars
def eval(self, expr):
value = self.lmp_print('"$(%s)"' % expr).strip()
try:
return float(value)
except ValueError:
return value
def _split_values(self, line):
return [x.strip() for x in line.split(',')]
def _get_pair(self, value):
return [x.strip() for x in value.split('=')]
def _parse_info_system(self, output):
lines = output[6:-2]
system = {}
for line in lines:
if line.startswith("Units"):
system['units'] = self._get_pair(line)[1]
elif line.startswith("Atom style"):
system['atom_style'] = self._get_pair(line)[1]
elif line.startswith("Atom map"):
system['atom_map'] = self._get_pair(line)[1]
elif line.startswith("Atoms"):
parts = self._split_values(line)
system['natoms'] = int(self._get_pair(parts[0])[1])
system['ntypes'] = int(self._get_pair(parts[1])[1])
system['style'] = self._get_pair(parts[2])[1]
elif line.startswith("Kspace style"):
system['kspace_style'] = self._get_pair(line)[1]
elif line.startswith("Dimensions"):
system['dimensions'] = int(self._get_pair(line)[1])
elif line.startswith("Orthogonal box"):
system['orthogonal_box'] = [float(x) for x in self._get_pair(line)[1].split('x')]
elif line.startswith("Boundaries"):
system['boundaries'] = self._get_pair(line)[1]
elif line.startswith("xlo"):
keys, values = [self._split_values(x) for x in self._get_pair(line)]
for key, value in zip(keys, values):
system[key] = float(value)
elif line.startswith("ylo"):
keys, values = [self._split_values(x) for x in self._get_pair(line)]
for key, value in zip(keys, values):
system[key] = float(value)
elif line.startswith("zlo"):
keys, values = [self._split_values(x) for x in self._get_pair(line)]
for key, value in zip(keys, values):
system[key] = float(value)
elif line.startswith("Molecule type"):
system['molecule_type'] = self._get_pair(line)[1]
elif line.startswith("Bonds"):
parts = self._split_values(line)
system['nbonds'] = int(self._get_pair(parts[0])[1])
system['nbondtypes'] = int(self._get_pair(parts[1])[1])
system['bond_style'] = self._get_pair(parts[2])[1]
elif line.startswith("Angles"):
parts = self._split_values(line)
system['nangles'] = int(self._get_pair(parts[0])[1])
system['nangletypes'] = int(self._get_pair(parts[1])[1])
system['angle_style'] = self._get_pair(parts[2])[1]
elif line.startswith("Dihedrals"):
parts = self._split_values(line)
system['ndihedrals'] = int(self._get_pair(parts[0])[1])
system['nangletypes'] = int(self._get_pair(parts[1])[1])
system['dihedral_style'] = self._get_pair(parts[2])[1]
elif line.startswith("Impropers"):
parts = self._split_values(line)
system['nimpropers'] = int(self._get_pair(parts[0])[1])
system['nimpropertypes'] = int(self._get_pair(parts[1])[1])
system['improper_style'] = self._get_pair(parts[2])[1]
return system
def _parse_info_communication(self, output):
lines = output[6:-3]
comm = {}
for line in lines:
if line.startswith("MPI library"):
comm['mpi_version'] = line.split(':')[1].strip()
elif line.startswith("Comm style"):
parts = self._split_values(line)
comm['comm_style'] = self._get_pair(parts[0])[1]
comm['comm_layout'] = self._get_pair(parts[1])[1]
elif line.startswith("Processor grid"):
comm['proc_grid'] = [int(x) for x in self._get_pair(line)[1].split('x')]
elif line.startswith("Communicate velocities for ghost atoms"):
comm['ghost_velocity'] = (self._get_pair(line)[1] == "yes")
elif line.startswith("Nprocs"):
parts = self._split_values(line)
comm['nprocs'] = int(self._get_pair(parts[0])[1])
comm['nthreads'] = int(self._get_pair(parts[1])[1])
return comm
def _parse_element_list(self, output):
lines = output[6:-3]
elements = []
for line in lines:
element_info = self._split_values(line.split(':')[1].strip())
element = {'name': element_info[0]}
for key, value in [self._get_pair(x) for x in element_info[1:]]:
element[key] = value
elements.append(element)
return elements
def _parse_groups(self, output):
lines = output[6:-3]
groups = []
group_pattern = re.compile(r"(?P<name>.+) \((?P<type>.+)\)")
for line in lines:
m = group_pattern.match(line.split(':')[1].strip())
group = {'name': m.group('name'), 'type': m.group('type')}
groups.append(group)
return groups
def lmp_print(self, s):
""" needed for Python2 compatibility, since print is a reserved keyword """
return self.__getattr__("print")(s)
def __dir__(self):
return ['angle_coeff', 'angle_style', 'atom_modify', 'atom_style', 'atom_style',
'bond_coeff', 'bond_style', 'boundary', 'change_box', 'communicate', 'compute',
'create_atoms', 'create_box', 'delete_atoms', 'delete_bonds', 'dielectric',
'dihedral_coeff', 'dihedral_style', 'dimension', 'dump', 'fix', 'fix_modify',
'group', 'improper_coeff', 'improper_style', 'include', 'kspace_modify',
'kspace_style', 'lattice', 'mass', 'minimize', 'min_style', 'neighbor',
'neigh_modify', 'newton', 'nthreads', 'pair_coeff', 'pair_modify',
'pair_style', 'processors', 'read', 'read_data', 'read_restart', 'region',
'replicate', 'reset_timestep', 'restart', 'run', 'run_style', 'thermo',
'thermo_modify', 'thermo_style', 'timestep', 'undump', 'unfix', 'units',
'variable', 'velocity', 'write_restart']
def __getattr__(self, name):
def handler(*args, **kwargs):
cmd_args = [name] + [str(x) for x in args]
with OutputCapture() as capture:
self.command(' '.join(cmd_args))
output = capture.output
if 'verbose' in kwargs and kwargs['verbose']:
print(output)
lines = output.splitlines()
if len(lines) > 1:
return lines
elif len(lines) == 1:
return lines[0]
return None
return handler
class IPyLammps(PyLammps):
"""
iPython wrapper for LAMMPS which adds embedded graphics capabilities
"""
def __init__(self,name="",cmdargs=None,ptr=None,comm=None):
super(IPyLammps, self).__init__(name=name,cmdargs=cmdargs,ptr=ptr,comm=comm)
def image(self, filename="snapshot.png", group="all", color="type", diameter="type",
size=None, view=None, center=None, up=None, zoom=1.0):
cmd_args = [group, "image", filename, color, diameter]
if size:
width = size[0]
height = size[1]
cmd_args += ["size", width, height]
if view:
theta = view[0]
phi = view[1]
cmd_args += ["view", theta, phi]
if center:
flag = center[0]
Cx = center[1]
Cy = center[2]
Cz = center[3]
cmd_args += ["center", flag, Cx, Cy, Cz]
if up:
Ux = up[0]
Uy = up[1]
Uz = up[2]
cmd_args += ["up", Ux, Uy, Uz]
if zoom:
cmd_args += ["zoom", zoom]
cmd_args.append("modify backcolor white")
self.write_dump(*cmd_args)
from IPython.core.display import Image
return Image('snapshot.png')
def video(self, filename):
from IPython.display import HTML
return HTML("<video controls><source src=\"" + filename + "\"></video>")