def getMolecules(self, group="all"):
"""Return a list containing all of the molecules in the specified group.
Parameters
----------
group : str
The name of the molecule group.
Returns
-------
molecules : [:class:`Molecule <BioSimSpace._SireWrappers.Molecule>`]
The list of molecules in the group.
"""
if type(group) is not str:
raise TypeError("'group' must be of type 'str'")
# Try to extract the molecule group.
try:
molgrp = self._sire_object.group(_SireMol.MGName(group))
except:
raise ValueError("No molecules in group '%s'" % group)
# Return a molecules container.
return _Molecules(molgrp.molecules())
def removeWaterMolecules(self):
"""Remove all of the water molecules from the system."""
# Get the list of water molecules.
waters = self.getWaterMolecules()
# Remove the molecules in the system.
self._sire_object.remove(waters._sire_object, _SireMol.MGName("all"))
# Reset the index mappings.
self._reset_mappings()
# Update the molecule numbers.
self._mol_nums = self._sire_object.molNums()
def removeMolecules(self, molecules):
"""Remove a molecule, or list of molecules from the system.
Parameters
----------
molecules : :class:`Molecule <BioSimSpace._SireWrappers.Molecule>`, \
:class:`Molecules <BioSimSpace._SireWrappers.Molecules>`, \
[:class:`Molecule <BioSimSpace._SireWrappers.Molecule>`]
A Molecule, Molecules object, or list of Molecule objects.
"""
# Whether the molecules are in a Sire container.
is_sire_container = False
# Convert tuple to a list.
if type(molecules) is tuple:
molecules = list(molecules)
# A Molecule object.
if type(molecules) is _Molecule:
molecules = [molecules]
# A Molecules object.
if type(molecules) is _Molecules:
is_sire_container = True
# A list of Molecule objects.
elif type(molecules) is list and all(isinstance(x, _Molecule) for x in molecules):
pass
# Invalid argument.
else:
raise TypeError("'molecules' must be of type 'BioSimSpace._SireWrappers.Molecule' "
"or a list of 'BioSimSpace._SireWrappers.Molecule' types.")
# Remove the molecules in the system.
if is_sire_container:
self._sire_object.remove(molecules._sire_object, _SireMol.MGName("all"))
else:
for mol in molecules:
self._sire_object.remove(mol._sire_object.number())
# Reset the index mappings.
self._reset_mappings()
# Update the molecule numbers.
self._mol_nums = self._sire_object.molNums()
def updateMolecules(self, molecules):
"""Update a molecule, or list of molecules in the system.
Parameters
----------
molecules : :class:`Molecule <BioSimSpace._SireWrappers.Molecule>`, \
[:class:`Molecule <BioSimSpace._SireWrappers.Molecule>`]
A Molecule, or list of Molecule objects.
"""
# Convert tuple to a list.
if type(molecules) is tuple:
molecules = list(molecules)
# A Molecule object.
if type(molecules) is _Molecule:
molecules = [molecules]
# A list of Molecule objects.
elif type(molecules) is list and all(isinstance(x, _Molecule) for x in molecules):
pass
# Invalid argument.
else:
raise TypeError("'molecules' must be of type 'BioSimSpace._SireWrappers.Molecule' "
"or a list of 'BioSimSpace._SireWrappers.Molecule' types.")
# Update each of the molecules.
# TODO: Currently the Sire.System.update method doesn't work correctly
# for certain changes to the Molecule molInfo object. As such, we remove
# the old molecule from the system, then add the new one in.
for mol in molecules:
try:
self._sire_object.update(mol._sire_object)
except:
self._sire_object.remove(mol._sire_object.number())
self._sire_object.add(mol._sire_object, _SireMol.MGName("all"))
# Reset the index mappings.
self._reset_mappings()
# Update the molecule numbers.
self._mol_nums = self._sire_object.molNums()
def getMolecules(self, group="all"):
"""Return a list containing all of the molecules in the specified group.
Parameters
----------
group : str
The name of the molecule group.
Returns
-------
molecules : [:class:`Molecule <BioSimSpace._SireWrappers.Molecule>`]
The list of molecules in the group.
"""
if type(group) is not str:
raise TypeError("'group' must be of type 'str'")
# Try to extract the molecule group.
try:
molgrp = self._sire_system.group(_SireMol.MGName(group))
except:
raise ValueError("No molecules in group '%s'" % group)
# Create a list to store the molecules.
mols = []
# Get a list of the MolNums in the group and sort them.
nums = molgrp.molNums()
# Loop over all of the molecules in the group and append to the list.
for num in nums:
mols.append(_Molecule(molgrp.molecule(num)))
# This is a merged molecule.
if mols[-1]._sire_molecule.hasProperty("is_perturbable"):
mols[-1]._is_merged = True
return mols
def addMolecules(self, molecules):
"""Add a molecule, or list of molecules to the system.
Parameters
----------
molecules : :class:`Molecule <BioSimSpace._SireWrappers.Molecule>`, \
[:class:`Molecule <BioSimSpace._SireWrappers.Molecule>`]
A Molecule, or list of Molecule objects.
"""
# Convert tuple to a list.
if type(molecules) is tuple:
molecules = list(molecules)
# A Molecule object.
if type(molecules) is _Molecule:
molecules = [molecules]
# A list of Molecule objects.
elif type(molecules) is list and all(isinstance(x, _Molecule) for x in molecules):
pass
# Invalid argument.
else:
raise TypeError("'molecules' must be of type 'BioSimSpace._SireWrappers.Molecule' "
"or a list of 'BioSimSpace._SireWrappers.Molecule' types.")
# The system is empty: create a new Sire system from the molecules.
if self._sire_system.nMolecules() == 0:
self._sire_system = self._createSireSystem(molecules)
# Otherwise, add the molecules to the existing "all" group.
else:
for mol in molecules:
self._sire_system.add(mol._sire_molecule, _SireMol.MGName("all"))
def addMolecules(self, molecules):
"""Add a molecule, or list of molecules to the system.
Parameters
----------
molecules : :class:`Molecule <BioSimSpace._SireWrappers.Molecule>`, \
:class:`Molecules <BioSimSpace._SireWrappers.Molecules>`, \
[:class:`Molecule <BioSimSpace._SireWrappers.Molecule>`], \
:class:`System <BioSimSpace._SireWrappers.System>`
A Molecule, Molecules object, a list of Molecule objects, or a System containing molecules.
"""
# Whether the molecules are in a Sire container.
is_sire_container = False
# Convert tuple to a list.
if type(molecules) is tuple:
molecules = list(molecules)
# A Molecule object.
if type(molecules) is _Molecule:
molecules = [molecules]
# A Molecules object.
if type(molecules) is _Molecules:
is_sire_container = True
# A System object.
elif type(molecules) is System:
is_sire_container = True
# A list of Molecule objects.
elif type(molecules) is list and all(isinstance(x, _Molecule) for x in molecules):
pass
# Invalid argument.
else:
raise TypeError("'molecules' must be of type 'BioSimSpace._SireWrappers.Molecule', "
", 'BioSimSpace._SireWrappers.System', or a list of "
"'BioSimSpace._SireWrappers.Molecule' types.")
# The system is empty: create a new Sire system from the molecules.
if self._sire_object.nMolecules() == 0:
self._sire_object = self._createSireSystem(molecules)
# Otherwise, add the molecules to the existing "all" group.
else:
if is_sire_container:
if type(molecules) is _Molecules:
molecules = molecules._sire_object
else:
try:
molecules = molecules._sire_object.at(_SireMol.MGNum(1))
except:
molecules = molecules._sire_object.molecules()
self._sire_object.add(molecules, _SireMol.MGName("all"))
else:
for mol in molecules:
self._sire_object.add(mol._sire_object, _SireMol.MGName("all"))
# Reset the index mappings.
self._reset_mappings()
# Update the molecule numbers.
self._mol_nums = self._sire_object.molNums()
def _initialise_runner(self, system0, system1):
"""Internral helper function to initialise the process runner.
Parameters
----------
system0 : :class:`System <BioSimSpace._SireWrappers.System>`
The system for the first free energy leg.
system1 : :class:`System <BioSimSpace._SireWrappers.System>`
The system for the second free energy leg.
"""
if type(system0) is not _System:
raise TypeError(
"'system0' must be of type 'BioSimSpace._SireWrappers.System'")
if type(system1) is not _System:
raise TypeError(
"'system1' must be of type 'BioSimSpace._SireWrappers.System'")
# Initialise lists to store the processes for each leg.
leg0 = []
leg1 = []
# Get the simulation type.
sim_type = self.__class__.__name__
# Store the working directories for the legs.
if sim_type == "Solvation":
self._dir0 = "%s/free" % self._work_dir
self._dir1 = "%s/vacuum" % self._work_dir
elif sim_type == "Binding":
self._dir0 = "%s/bound" % self._work_dir
self._dir1 = "%s/free" % self._work_dir
else:
raise TypeError("Unsupported FreeEnergy simulation: '%s'" %
sim_type)
# Try to get the water model property of the system.
try:
water_model = system0._sire_system.property(
"water_model").toString()
# Default to TIP3P.
except:
water_model = "tip3p"
if self._engine == "SOMD":
# Reformat all of the water molecules so that they match the expected
# AMBER topology template. (Required by SOMD.)
waters0 = _SireIO.setAmberWater(
system0._sire_system.search("water"), water_model)
waters1 = _SireIO.setAmberWater(
system1._sire_system.search("water"), water_model)
# Loop over all of the renamed water molecules, delete the old one
# from the system, then add the renamed one back in.
# TODO: This is a hack since the "update" method of Sire.System
# doesn't work properly at present.
system0.removeWaterMolecules()
system1.removeWaterMolecules()
for wat in waters0:
system0._sire_system.add(wat, _SireMol.MGName("all"))
for wat in waters1:
system1._sire_system.add(wat, _SireMol.MGName("all"))
# Get the lambda values from the protocol.
lam_vals = self._protocol.getLambdaValues()
# Loop over all of the lambda values.
for lam in lam_vals:
# Update the protocol lambda values.
self._protocol.setLambdaValues(lam=lam, lam_vals=lam_vals)
# Create and append the required processes for each leg.
# Nest the working directories inside self._work_dir.
# SOMD.
if self._engine == "SOMD":
# TODO: This is currently hard-coded to use SOMD with the CUDA platform.
leg0.append(
_Process.Somd(system0,
self._protocol,
platform="CUDA",
work_dir="%s/lambda_%5.4f" %
(self._dir0, lam)))
leg1.append(
_Process.Somd(system1,
self._protocol,
platform="CUDA",
work_dir="%s/lambda_%5.4f" %
(self._dir1, lam)))
# GROMACS.
elif self._engine == "GROMACS":
# TODO: This is currently hard-coded to use SOMD with the CUDA platform.
leg0.append(
_Process.Gromacs(system0,
self._protocol,
work_dir="%s/lambda_%5.4f" %
(self._dir0, lam)))
leg1.append(
_Process.Gromacs(system1,
self._protocol,
work_dir="%s/lambda_%5.4f" %
(self._dir1, lam)))
# Initialise the process runner. All processes have already been nested
# inside the working directory so no need to re-nest.
self._runner = _Process.ProcessRunner(leg0 + leg1,
work_dir=self._work_dir,
nest_dirs=False)
def _solvate(molecule,
box,
shell,
model,
num_point,
ion_conc,
is_neutral,
work_dir=None,
property_map={}):
"""Internal function to add solvent using 'gmx solvate'.
Parameters
----------
molecule : :class:`Molecule <BioSimSpace._SireWrappers.Molecule>`, \
:class:`System <BioSimSpace._SireWrappers.System>`
A molecule, or system of molecules.
box : [:class:`Length <BioSimSpace.Types.Length>`]
A list containing the box size in each dimension (in nm).
shell : :class:`Length` <BioSimSpace.Types.Length>`
Thickness of the water shell around the solute.
model : str
The name of the water model.
num_point : int
The number of atoms in the water model.
ion_conc : float
The ion concentration in (mol per litre).
is_neutral : bool
Whether to neutralise the system.
work_dir : str
The working directory for the process.
property_map : dict
A dictionary that maps system "properties" to their user defined
values. This allows the user to refer to properties with their
own naming scheme, e.g. { "charge" : "my-charge" }
Returns
-------
system : :class:`System <BioSimSpace._SireWrappers.System>`
The solvated system.
"""
if molecule is not None:
# Store the centre of the molecule.
center = molecule._getAABox(property_map).center()
# Work out the vector from the centre of the molecule to the centre of the
# water box, converting the distance in each direction to Angstroms.
vec = []
for x, y in zip(box, center):
vec.append(0.5 * x.angstroms().magnitude() - y)
# Translate the molecule. This allows us to create a water box
# around the molecule.
molecule.translate(vec, property_map)
if type(molecule) is _System:
# Reformat all of the water molecules so that they match the
# expected GROMACS topology template.
waters = _SireIO.setGromacsWater(
molecule._sire_system.search("water"), model)
# Loop over all of the renamed water molecules, delete the old one
# from the system, then add the renamed one back in.
# TODO: This is a hack since the "update" method of Sire.System
# doesn't work properly at present.
molecule.removeWaterMolecules()
for wat in waters:
molecule._sire_system.add(wat, _SireMol.MGName("all"))
# Create a temporary working directory and store the directory name.
if work_dir is None:
tmp_dir = _tempfile.TemporaryDirectory()
work_dir = tmp_dir.name
# Run the solvation in the working directory.
with _Utils.cd(work_dir):
# Create the gmx command.
if num_point == 3:
mod = "spc216"
else:
mod = model
command = "%s solvate -cs %s" % (_gmx_exe, mod)
if molecule is not None:
# Write the molecule/system to a GRO files.
_IO.saveMolecules("input", molecule, "gro87")
_os.rename("input.gro87", "input.gro")
# Update the command.
command += " -cp input.gro"
# Add the box information.
if box is not None:
command += " -box %f %f %f" % (box[0].nanometers().magnitude(),
box[1].nanometers().magnitude(),
box[2].nanometers().magnitude())
# Add the shell information.
if shell is not None:
command += " -shell %f" % shell.nanometers().magnitude()
# Just add box information.
else:
command += " -box %f %f %f" % (box[0].nanometers().magnitude(),
box[1].nanometers().magnitude(),
box[2].nanometers().magnitude())
# Add the output file.
command += " -o output.gro"
with open("README.txt", "w") as file:
# Write the command to file.
file.write("# gmx solvate was run with the following command:\n")
file.write("%s\n" % command)
# Create files for stdout/stderr.
stdout = open("solvate.out", "w")
stderr = open("solvate.err", "w")
# Run gmx solvate as a subprocess.
proc = _subprocess.run(command,
shell=True,
stdout=stdout,
stderr=stderr)
stdout.close()
stderr.close()
# gmx doesn't return sensible error codes, so we need to check that
# the expected output was generated.
if not _os.path.isfile("output.gro"):
raise RuntimeError("'gmx solvate failed to generate output!")
# Extract the water lines from the GRO file.
water_lines = []
with open("output.gro", "r") as file:
for line in file:
if _re.search("SOL", line):
# Store the SOL atom record.
water_lines.append(line)
# Add any box information. This is the last line in the GRO file.
water_lines.append(line)
# Write a GRO file that contains only the water atoms.
if len(water_lines) - 1 > 0:
with open("water.gro", "w") as file:
file.write("BioSimSpace %s water box\n" % model.upper())
file.write("%d\n" % (len(water_lines) - 1))
for line in water_lines:
file.write("%s" % line)
else:
raise ValueError(
"No water molecules were generated. Try increasing "
"the 'box' size or 'shell' thickness.")
# Create a TOP file for the water model. By default we use the Amber03
# force field to generate a dummy topology for the water model.
with open("water_ions.top", "w") as file:
file.write("#define FLEXIBLE 1\n\n")
file.write("; Include AmberO3 force field\n")
file.write('#include "amber03.ff/forcefield.itp"\n\n')
file.write("; Include %s water topology\n" % model.upper())
file.write('#include "amber03.ff/%s.itp"\n\n' % model)
file.write("; Include ions\n")
file.write('#include "amber03.ff/ions.itp"\n\n')
file.write("[ system ] \n")
file.write("BioSimSpace %s water box\n\n" % model.upper())
file.write("[ molecules ] \n")
file.write(";molecule name nr.\n")
file.write("SOL %d\n" %
((len(water_lines) - 1) / num_point))
# Load the water box.
water = _IO.readMolecules(["water.gro", "water_ions.top"])
# Create a new system by adding the water to the original molecule.
if molecule is not None:
# Translate the molecule and water back to the original position.
vec = [-x for x in vec]
molecule.translate(vec, property_map)
water.translate(vec)
if type(molecule) is _System:
# Extract the non-water molecules from the original system.
non_waters = [
mol for mol in molecule.getMolecules()
if not mol.isWater()
]
# Create a system by adding these to the water molecules from
# gmx solvate, which will include the original waters.
system = _System(non_waters + water.getMolecules())
else:
system = molecule + water.getMolecules()
# Add all of the water box properties to the new system.
for prop in water._sire_system.propertyKeys():
prop = property_map.get(prop, prop)
# Add the space property from the water system.
system._sire_system.setProperty(
prop, water._sire_system.property(prop))
else:
system = water
# Now we add ions to the system and neutralise the charge.
if ion_conc > 0 or is_neutral:
# Write the molecule + water system to file.
_IO.saveMolecules("solvated", system, "gro87")
_IO.saveMolecules("solvated", system, "grotop")
_os.rename("solvated.gro87", "solvated.gro")
_os.rename("solvated.grotop", "solvated.top")
# First write an mdp file.
with open("ions.mdp", "w") as file:
file.write("; Neighbour searching\n")
file.write("cutoff-scheme = Verlet\n")
file.write("rlist = 1.1\n")
file.write("pbc = xyz\n")
file.write("verlet-buffer-tolerance = -1\n")
file.write("\n; Electrostatics\n")
file.write("coulombtype = cut-off\n")
file.write("\n; VdW\n")
file.write("rvdw = 1.0\n")
# Create the grompp command.
command = "%s grompp -f ions.mdp -po ions.out.mdp -c solvated.gro -p solvated.top -o ions.tpr" % _gmx_exe
with open("README.txt", "a") as file:
# Write the command to file.
file.write(
"\n# gmx grompp was run with the following command:\n")
file.write("%s\n" % command)
# Create files for stdout/stderr.
stdout = open("grommp.out", "w")
stderr = open("grommp.err", "w")
# Run grompp as a subprocess.
proc = _subprocess.run(command,
shell=True,
stdout=stdout,
stderr=stderr)
stdout.close()
stderr.close()
# Flag whether to break out of the ion adding stage.
is_break = False
# Check for the tpr output file.
if not _os.path.isfile("ions.tpr"):
if shell is None:
raise RuntimeError(
"'gmx grommp' failed to generate output! "
"Perhaps your box is too small?")
else:
is_break = True
_warnings.warn(
"Unable to achieve target ion concentration, try using "
"'box' option instead of 'shell'.")
# Only continue if grommp was successful. This allows us to skip the remainder
# of the code if the ion addition failed when the 'shell' option was chosen, i.e.
# because the estimated simulation box was too small.
if not is_break:
is_break = False
# The ion concentration is unset.
if ion_conc == 0:
# Get the current molecular charge.
charge = system.charge()
# Round to the nearest integer value.
charge = round(charge.magnitude())
# Create the genion command.
command = "echo SOL | %s genion -s ions.tpr -o solvated_ions.gro -p solvated.top -neutral" % _gmx_exe
# Add enough counter ions to neutralise the charge.
if charge > 0:
command += " -nn %d" % abs(charge)
else:
command += " -np %d" % abs(charge)
else:
# Create the genion command.
command = "echo SOL | %s genion -s ions.tpr -o solvated_ions.gro -p solvated.top -%s -conc %f" \
% (_gmx_exe, "neutral" if is_neutral else "noneutral", ion_conc)
with open("README.txt", "a") as file:
# Write the command to file.
file.write(
"\n# gmx genion was run with the following command:\n")
file.write("%s\n" % command)
# Create files for stdout/stderr.
stdout = open("genion.out", "w")
stderr = open("genion.err", "w")
# Run genion as a subprocess.
proc = _subprocess.run(command,
shell=True,
stdout=stdout,
stderr=stderr)
stdout.close()
stderr.close()
# Check for the output GRO file.
if not _os.path.isfile("solvated_ions.gro"):
if shell is None:
raise RuntimeError(
"'gmx genion' failed to add ions! Perhaps your box is too small?"
)
else:
is_break = True
_warnings.warn(
"Unable to achieve target ion concentration, try using "
"'box' option instead of 'shell'.")
if not is_break:
# Counters for the number of SOL, NA, and CL atoms.
num_sol = 0
num_na = 0
num_cl = 0
# We now need to loop through the GRO file to extract the lines
# corresponding to water or ion atoms.
water_ion_lines = []
with open("solvated_ions.gro", "r") as file:
for line in file:
# This is a Sodium atom.
if _re.search("NA", line):
water_ion_lines.append(line)
num_na += 1
# This is a Chlorine atom.
if _re.search("CL", line):
water_ion_lines.append(line)
num_cl += 1
# This is a water atom.
elif _re.search("SOL", line):
water_ion_lines.append(line)
num_sol += 1
# Add any box information. This is the last line in the GRO file.
water_ion_lines.append(line)
# Write a GRO file that contains only the water and ion atoms.
if len(water_ion_lines) - 1 > 0:
with open("water_ions.gro", "w") as file:
file.write("BioSimSpace %s water box\n" %
model.upper())
file.write("%d\n" % (len(water_ion_lines) - 1))
for line in water_ion_lines:
file.write("%s" % line)
# Ions have been added. Update the TOP file fo the water model
# with the new atom counts.
if num_na > 0 or num_cl > 0:
with open("water_ions.top", "w") as file:
file.write("#define FLEXIBLE 1\n\n")
file.write("; Include AmberO3 force field\n")
file.write(
'#include "amber03.ff/forcefield.itp"\n\n')
file.write("; Include %s water topology\n" %
model.upper())
file.write('#include "amber03.ff/%s.itp"\n\n' %
model)
file.write("; Include ions\n")
file.write('#include "amber03.ff/ions.itp"\n\n')
file.write("[ system ] \n")
file.write("BioSimSpace %s water box\n\n" %
model.upper())
file.write("[ molecules ] \n")
file.write(";molecule name nr.\n")
file.write("SOL %d\n" %
(num_sol / num_point))
if num_na > 0:
file.write("NA %d\n" % num_na)
if num_cl > 0:
file.write("CL %d\n" % num_cl)
# Load the water/ion box.
water_ions = _IO.readMolecules(
["water_ions.gro", "water_ions.top"])
# Create a new system by adding the water to the original molecule.
if molecule is not None:
if type(molecule) is _System:
# Extract the non-water molecules from the original system.
non_waters = [
mol for mol in molecule.getMolecules()
if not mol.isWater()
]
# Create a system by adding these to the water and ion
# molecules from gmx solvate, which will include the
# original waters.
system = _System(non_waters +
water_ions.getMolecules())
else:
system = molecule + water_ions.getMolecules()
# Add all of the water molecules' properties to the new system.
for prop in water_ions._sire_system.propertyKeys():
prop = property_map.get(prop, prop)
# Add the space property from the water system.
system._sire_system.setProperty(
prop, water_ions._sire_system.property(prop))
else:
system = water_ions
# Store the name of the water model as a system property.
system._sire_system.setProperty("water_model", _SireBase.wrap(model))
return system