def filter_function(data_row):
n_components = data_row["N Components"]
for index in range(n_components):
smiles = data_row[f"Component {index + 1}"]
molecule = Molecule.from_smiles(smiles, allow_undefined_stereo=True)
if not all([x.element.symbol in allowed_elements for x in molecule.atoms]):
return False
return True
def smiles_to_svg(smiles: str, torsion_indices: (int, int), image_width: int = 200, image_height: int = 200) -> str:
"""Renders a 2D representation of a molecule based on its SMILES representation as
an SVG string.
Parameters
----------
smiles
The SMILES pattern.
torsion_indices
The torsion indices for the molecule.
image_width
The width to make the final SVG.
image_height
The height to make the final SVG.
Returns
-------
The 2D SVG representation.
"""
# Parse the SMILES into an RDKit molecule
smiles_parser = Chem.rdmolfiles.SmilesParserParams()
smiles_parser.removeHs = False
oe_conformed = False
try:
oe_molecule, status = smiles2oemol(smiles)
openff_molecule = Molecule.from_openeye(oe_molecule)
rdkit_molecule = openff_molecule.to_rdkit()
oe_conformed = True
except:
rdkit_molecule = Chem.MolFromSmiles(smiles, smiles_parser)
# Generate a set of 2D coordinates.
Chem.rdDepictor.Compute2DCoords(rdkit_molecule)
drawer = rdMolDraw2D.MolDraw2DSVG(image_width, image_height)
torsion_bonds = []
if oe_conformed:
for i in range(len(torsion_indices) - 1):
if rdkit_molecule.GetBondBetweenAtoms(torsion_indices[i], torsion_indices[i+1]):
torsion_bonds.append(rdkit_molecule.GetBondBetweenAtoms(torsion_indices[i], torsion_indices[i+1]).GetIdx())
rdMolDraw2D.PrepareAndDrawMolecule(drawer, rdkit_molecule, highlightBonds = torsion_bonds)
drawer.FinishDrawing()
svg_content = drawer.GetDrawingText()
return svg_content
def setUp(self):
# TODO: Harmonize with test_system_generator.py infrastructure
# Read test molecules
from openforcefield.topology import Molecule
filename = get_data_filename("minidrugbank/MiniDrugBank-without-unspecified-stereochemistry.sdf")
molecules = Molecule.from_file(filename, allow_undefined_stereo=True)
# Filter molecules as appropriate
self.molecules = self.filter_molecules(molecules)
# Suppress DEBUG logging from various packages
import logging
for name in ['parmed', 'matplotlib']:
logging.getLogger(name).setLevel(logging.WARNING)
def test_ff_mol2(test_ff, mol2_fnm):
"""
Test creating system with mol2 file
"""
from openforcefield.topology import Molecule as Off_Molecule
from openforcefield.topology import Topology as Off_Topology
try:
off_molecule = Off_Molecule.from_file(mol2_fnm)
off_topology = Off_Topology.from_molecules(off_molecule)
test_ff.create_openmm_system(off_topology)
molecule_labels = test_ff.label_molecules(off_topology)[0]
except Exception as e:
return False, str(e), None
return True, '', molecule_labels
def test_load_one_mol_sdf_without_charge(self, toolkit):
"""Test loading one molecule from a .sdf file WITHOUT charges"""
registry = make_registry(toolkit)
ethanol = get_data_file_path("molecules/ethanol.sdf")
assert Molecule.from_file(ethanol).partial_charges is None
mols_out = generate_conformers(
molecule=ethanol,
forcefield="openff-1.0.0.offxml",
registry=registry,
)
assert len(mols_out) > 1
assert mols_out[0].partial_charges is not None
def checkTorsion(molList, ff_name):
"""
Take mollist and check if the molecules in a list match a specific torsion id
Parameters
----------
molList : List of objects
List of oemols with datatags generated in genData function
Returns
-------
molList : list of objects
List of oemol objects that have a datatag "IDMatch" that contain the torsion id
involved in the QCA torsion drive
"""
matches = []
count = 0
mols = []
for mol in molList:
molecule = Molecule.from_mapped_smiles(mol.GetData("cmiles"))
topology = Topology.from_molecules(molecule)
# Let's label using the Parsley force field
forcefield = ForceField(ff_name)
# Run the molecule labeling
molecule_force_list = forcefield.label_molecules(topology)
params = []
# Print out a formatted description of the torsion parameters applied to this molecule
for mol_idx, mol_forces in enumerate(molecule_force_list):
# print(f'Forces for molecule {mol_idx}')
for force_tag, force_dict in mol_forces.items():
if force_tag == "ProperTorsions":
for (atom_indices, parameter) in force_dict.items():
params.append(parameter.id)
if atom_indices == mol.GetData("TDindices") or tuple(
reversed(atom_indices)
) == mol.GetData("TDindices"):
count += 1
mol.SetData("IDMatch", parameter.id)
mols.append(mol)
print(
"Out of "
+ str(len(molList))
+ " molecules, "
+ str(count)
+ " were processed with checkTorsion()"
)
return mols
def get_energies(self, resolution=30, get_thetas=False):
"""
It returns the energies of this energetic profile calculator.
Parameters
----------
resolution : float
The resolution, in degrees, that is applied when rotating
the dihedral rotatable bond. Default is 30 degrees
get_thetas : bool
Whether to return thetas (dihedral angles) or not. Default
is False
Returns
-------
dihedral_energies : a simtk.unit.Quantity object
The array of energies represented with a simtk's Quantity
object
thetas : list[float]
The array of thetas, only if requested in the corresponding
function parameter
"""
mol_with_conformers = \
self.dihedral_benchmark.generate_dihedral_conformers(
resolution)
from openforcefield.topology import Molecule
mol = Molecule.from_rdkit(mol_with_conformers)
dihedral_energies = list()
for i, conformer in enumerate(mol.conformers):
energy = self._calc_energy(conformer)
dihedral_energies.append(energy)
if get_thetas:
from rdkit.Chem import rdMolTransforms
thetas = list()
for conf in mol_with_conformers.GetConformers():
thetas.append(
rdMolTransforms.GetDihedralDeg(
conf, *self.dihedral_benchmark.atom_indexes))
return dihedral_energies, thetas
return dihedral_energies
def _build_molecule_arrays(self):
"""Converts the input substance into a list of molecules and a list
of counts for how many of each there should be as determined by the
`max_molecules` input and the substances respective mole fractions.
Returns
-------
list of openforcefield.topology.Molecule
The list of molecules.
list of int
The number of each molecule which should be added to the system.
"""
from openforcefield.topology import Molecule
molecules = []
for component in self.substance.components:
molecule = Molecule.from_smiles(component.smiles)
molecules.append(molecule)
# Determine how many molecules of each type will be present in the system.
molecules_per_component = self.substance.get_molecules_per_component(
self.max_molecules, count_exact_amount=self.count_exact_amount)
number_of_molecules = [0] * self.substance.number_of_components
for index, component in enumerate(self.substance.components):
number_of_molecules[index] = molecules_per_component[
component.identifier]
total_n_molecules = sum(number_of_molecules)
if not self.count_exact_amount:
n_exact_molecule = sum(
amount.value for component in self.substance.components
for amount in self.substance.amounts[component.identifier]
if isinstance(amount, ExactAmount))
total_n_molecules -= n_exact_molecule
if total_n_molecules > self.max_molecules:
raise ValueError(
f"The number of molecules to create ({total_n_molecules}) is "
f"greater than the maximum number requested ({self.max_molecules})."
)
return molecules, number_of_molecules, None
def test_OEMol_to_omm_ff(molecule=smiles_to_oemol('CC')):
"""
Generating openmm objects for simulation from an OEMol object
Parameters
----------
molecule : openeye.oechem.OEMol
Returns
-------
system : openmm.System
openmm system object
positions : unit.quantity
positions of the system
topology : app.topology.Topology
openmm compatible topology object
"""
import simtk.openmm.app as app
import simtk.unit as unit
from perses.utils.openeye import OEMol_to_omm_ff
from simtk import openmm
from openmmforcefields.generators import SystemGenerator
from openforcefield.topology import Molecule
#default arguments for SystemGenerators
barostat = None
forcefield_files = ['amber14/protein.ff14SB.xml', 'amber14/tip3p.xml']
forcefield_kwargs = {
'removeCMMotion': False,
'ewaldErrorTolerance': 1e-4,
'nonbondedMethod': app.NoCutoff,
'constraints': app.HBonds,
'hydrogenMass': 4 * unit.amus
}
small_molecule_forcefield = 'gaff-2.11'
system_generator = SystemGenerator(
forcefields=forcefield_files,
barostat=barostat,
forcefield_kwargs=forcefield_kwargs,
small_molecule_forcefield=small_molecule_forcefield,
molecules=[Molecule.from_openeye(molecule)],
cache=None)
system, positions, topology = OEMol_to_omm_ff(molecule, system_generator)
assert (type(system) == type(openmm.System())
), "An openmm.System has not been generated from OEMol_to_omm_ff()"
return system, positions, topology
def test_fragmentation_apply():
"""
Make sure that fragmentation is working.
"""
fragmenter = workflow_components.WBOFragmenter()
assert fragmenter.is_available()
# check that a molecule with no rotatable bonds fails if we dont want the parent back
benzene = Molecule.from_file(get_data("benzene.sdf"), "sdf")
result = fragmenter.apply([benzene, ], processors=1)
assert result.n_molecules == 0
# now try ethanol
ethanol = Molecule.from_file(get_data("methanol.sdf"), "sdf")
fragmenter.include_parent = True
result = fragmenter.apply([ethanol, ], processors=1)
assert result.n_molecules == 1
# now try a molecule which should give fragments
diphenhydramine = Molecule.from_smiles("O(CCN(C)C)C(c1ccccc1)c2ccccc2")
fragmenter.include_parent = False
result = fragmenter.apply([diphenhydramine, ], processors=1)
assert result.n_molecules == 4
for molecule in result.molecules:
assert "dihedrals" in molecule.properties
def generate_fitting_task(
self,
molecule: off.Molecule,
fragment: bool,
attributes: MoleculeAttributes,
fragment_parent_mapping: Optional[Dict[int, int]] = None,
dihedrals: Optional[List[Tuple[int, int, int, int]]] = None,
) -> Union[TorsionTask, OptimizationTask, HessianTask]:
"""
For the given collection workflow generate a task schema for the input molecule.
"""
if molecule.n_conformers < self.target_conformers:
molecule.generate_conformers(n_conformers=self.target_conformers,
clear_existing=False)
# build a dict of the data
data = dict(
name=self.collection_workflow,
attributes=attributes,
provenance=self.provenance(),
fragment=fragment,
fragment_parent_mapping=fragment_parent_mapping,
molecule=molecule,
dihedrals=dihedrals,
)
if self.collection_workflow == "torsion1d":
task = TorsionTask(**data)
elif self.collection_workflow == "optimization":
task = OptimizationTask(**data)
elif self.collection_workflow == "hessian":
task = HessianTask(**data)
else:
raise NotImplementedError(
f"The collection workflow {self.collection_workflow} is not supported."
)
return task
def biphenyl_workflow(target) -> OptimizationSchema:
"""
Create a workflow schema which targets the rotatable bond in ethane.
"""
mol = Molecule.from_file(get_data("biphenyl.sdf"), "sdf")
workflow = WorkflowFactory()
# turn off bespoke terms we want fast fitting
workflow.generate_bespoke_terms = False
workflow.expand_torsion_terms = False
fb = ForceBalanceOptimizer()
target = target()
fb.set_optimization_target(target=target)
workflow.set_optimizer(optimizer=fb)
schema = workflow.fitting_schema_from_molecules(molecules=mol)
return schema.tasks[0]
def get_smirnoff_params(mol: oechem.OEMol) -> {"id": ["atom_indices"]}:
"""For the given molecule, finds the SMIRNOFF params and their atom indices"""
off_mol = Molecule.from_openeye(mol, allow_undefined_stereo=True)
try:
topology = Topology.from_molecules(off_mol)
except Exception as e:
return {}
molecule_force_list = utilize_params_util.SMIRNOFF.label_molecules(topology)
params = defaultdict(list)
for force_tag, force_dict in molecule_force_list[0].items():
for (atom_index, parameter) in force_dict.items():
params[parameter.id].append(atom_index)
return params
def label_molecule(self, molecule: off.Molecule) -> Dict[str, str]:
"""
Type the molecule with the forcefield and return a molecule parameter dictionary.
Parameters
----------
molecule: off.Molecule
The openforcefield.topology.Molecule that should be labeled by the forcefield.
Returns
-------
Dict[str, str]
A dictionary of each parameter assigned to molecule organised by parameter handler type.
"""
return self.forcefield.label_molecules(molecule.to_topology())[0]
def test_to_file_fileformat_invalid(self):
"""
Checks for invalid file format
"""
from openforcefield.tests.test_forcefield import create_ethanol
from openforcefield.topology import Molecule, Topology
topology = Topology()
mol = Molecule.from_pdb_and_smiles(
get_data_file_path("systems/test_systems/1_ethanol.pdb"), "CCO")
topology.add_molecule(mol)
positions = mol.conformers[0]
fname = "ethanol_file.pdb"
with pytest.raises(NotImplementedError):
topology.to_file(fname, positions, file_format="AbC")
def filter_function(data_row):
n_components = data_row["N Components"]
for index in range(n_components):
smiles = data_row[f"Component {index + 1}"]
molecule = Molecule.from_smiles(smiles, allow_undefined_stereo=True)
if np.isclose(sum([atom.formal_charge for atom in molecule.atoms]), 0.0):
continue
return False
return True
def test_from_openmm_duplicate_unique_mol(self):
"""Check that a DuplicateUniqueMoleculeError is raised if we try to pass in two indistinguishably unique mols"""
from simtk.openmm import app
pdbfile = app.PDBFile(
get_data_file_path(
'systems/packmol_boxes/cyclohexane_ethanol_0.4_0.6.pdb'))
molecules = [
Molecule.from_file(get_data_file_path(name))
for name in ('molecules/ethanol.mol2',
'molecules/ethanol_reordered.mol2',
'molecules/cyclohexane.mol2')
]
with self.assertRaises(DuplicateUniqueMoleculeError) as context:
topology = Topology.from_openmm(pdbfile.topology,
unique_molecules=molecules)
def _get_rdkit_mcs_mapping(fragment: Molecule, parent: Molecule) -> Dict[int, int]:
"""
Use rdkit MCS function to find the maximum mapping between the fragment and parent molecule.
"""
from rdkit import Chem
from rdkit.Chem import rdFMCS
parent_rdkit = parent.to_rdkit()
fragment_rdkit = fragment.to_rdkit()
mcs = rdFMCS.FindMCS(
[parent_rdkit, fragment_rdkit],
atomCompare=rdFMCS.AtomCompare.CompareElements,
bondCompare=rdFMCS.BondCompare.CompareAny,
ringMatchesRingOnly=True,
completeRingsOnly=True,
)
# make a new molecule from the mcs
match_mol = Chem.MolFromSmarts(mcs.smartsString)
# get the mcs parent/fragment mapping
matches_parent = parent_rdkit.GetSubstructMatch(match_mol)
matches_fragment = fragment_rdkit.GetSubstructMatch(match_mol)
mapping = dict(zip(matches_fragment, matches_parent))
return mapping
def gen_tid_molecules_list(molecule_attributes, molecules_list_dict,
forcefield):
# gen dictionary with keys, including all tids in the input forcefield
ff_torsion_param_list = forcefield.get_parameter_handler(
'ProperTorsions').parameters
tid_molecules_list = {}
for torsion_param in ff_torsion_param_list:
tid_molecules_list[torsion_param.id] = []
for idx, (mol_index, mol_attr) in enumerate(molecule_attributes.items()):
mapped_smiles = mol_attr[
'canonical_isomeric_explicit_hydrogen_mapped_smiles']
qcjson_mol = molecules_list_dict[mol_index][0]
oemol = cmiles.utils.load_molecule(qcjson_mol)
off_mol = Off_Molecule.from_openeye(oemol, allow_undefined_stereo=True)
torsions_coverage, center_tids = smirnoff_analysis_torsions(
forcefield, off_mol)
filtered_torsions_coverage = filter_torsions_coverage(
torsions_coverage, oemol)
for tid, indices_list in filtered_torsions_coverage.items():
for indices in indices_list:
covered_tids = []
i, j, k, l = indices
tids = center_tids[tuple(sorted([j, k]))]
for i in tids:
if i not in covered_tids:
covered_tids.append(i)
tid_molecules_list[tid].append({
'mol_index': mol_index,
'indices': indices,
'covered_tids': covered_tids
})
print("\n## Torsion parameter: matched molecules ##\n" + '-' * 90)
print(
f"{'idx':<7} {'ID':7s} {'SMIRKS Pattern':70s} {'Number of molecules matched'}"
)
for idx, (tid, molecules_list) in enumerate(tid_molecules_list.items()):
torsion_param = get_torsion_definition(ff_torsion_param_list, tid)
print(
f'{idx:<7} {torsion_param.id:7s} {torsion_param.smirks:70s} {len(molecules_list)}'
)
print('-' * 90)
return tid_molecules_list
def select_torsions(molecules_list_dict,
molecule_attributes,
forcefield,
target_coverage=3):
torsions_dict = {}
smirks_torsions_counter = Counter()
i_mol = 0
for mol_index, mol_attr in molecule_attributes.items():
print(f'{i_mol:<7d}: {mol_index}')
i_mol += 1
mapped_smiles = mol_attr[
'canonical_isomeric_explicit_hydrogen_mapped_smiles']
# round trip from QCFractal molecule to OpenEye molecule then to Off Molecule
# this is needed for now to ensure atom indeices are consistent
qcjson_mol = molecules_list_dict[mol_index][0]
oemol = cmiles.utils.load_molecule(qcjson_mol)
off_mol = Off_Molecule.from_openeye(oemol, allow_undefined_stereo=True)
torsions_coverage = smirnoff_analyze_torsions(forcefield, off_mol)
for smirks, torsion_idx_list in torsions_coverage.items():
for atom_indices in torsion_idx_list:
if smirks_torsions_counter[smirks] < target_coverage:
smirks_torsions_counter[smirks] += 1
canonical_torsion_index = cmiles.utils.to_canonical_label(
mapped_smiles, atom_indices)
torsions_dict[canonical_torsion_index] = {
'initial_molecules': molecules_list_dict[mol_index],
'atom_indices': [atom_indices],
'attributes': mol_attr,
}
print(
f" - torsion {atom_indices} added for smirks {smirks}"
)
else:
print(
f" - torsion {atom_indices} skipped because {smirks} have {smirks_torsions_counter[smirks]} already"
)
print("\n## Selected Torsion Coverage ##\n" + '-' * 90)
ff_torsion_param_list = forcefield.get_parameter_handler(
'ProperTorsions').parameters
n_covered = 0
for param in ff_torsion_param_list:
count = smirks_torsions_counter[param.smirks]
print(f"{param.smirks:80s} : {count:7d}")
if count > 0:
n_covered += 1
print('-' * 90)
print(f'{n_covered} / {len(ff_torsion_param_list)} torsion SMIRKs covered')
return torsions_dict
def smirnoff_analyze_parameter_coverage(forcefield, tgt_opts):
printcool("SMIRNOFF Parameter Coverage Analysis")
assert hasattr(forcefield, 'offxml'), "Only SMIRNOFF Force Field is supported"
parameter_assignment_data = defaultdict(list)
parameter_counter = Counter()
# The openforcefield.typing.engines.smirnoff.ForceField object should now be contained in forcebalance.forcefield.FF
ff = forcefield.openff_forcefield
# analyze each target
for tgt_option in tgt_opts:
target_path = os.path.join('targets', tgt_option['name'])
# aggregate mol2 file paths from all targets
mol2_paths = []
if tgt_option['type'] == 'OPTGEOTARGET_SMIRNOFF':
# parse optgeo_options_txt and get the names of the mol2 files
optgeo_options_txt = os.path.join(target_path, tgt_option['optgeo_options_txt'])
sys_opts = forcebalance.opt_geo_target.OptGeoTarget.parse_optgeo_options(optgeo_options_txt)
mol2_paths = [os.path.join(target_path,fnm) for sysopt in sys_opts.values() for fnm in sysopt['mol2']]
elif tgt_option['type'].endswith('_SMIRNOFF'):
mol2_paths = [os.path.join(target_path,fnm) for fnm in tgt_option['mol2']]
# analyze SMIRKs terms
for mol_fnm in mol2_paths:
# we work with one file at a time to avoid the topology sliently combine "same" molecules
openff_mol = OffMolecule.from_file(mol_fnm)
off_topology = OffTopology.from_molecules([openff_mol])
molecule_force_list = ff.label_molecules(off_topology)
for mol_idx, mol_forces in enumerate(molecule_force_list):
for force_tag, force_dict in mol_forces.items():
# e.g. force_tag = 'Bonds'
for atom_indices, parameter in force_dict.items():
param_dict = {'id': parameter.id, 'smirks': parameter.smirks, 'type':force_tag, 'atoms': list(atom_indices),}
parameter_assignment_data[mol_fnm].append(param_dict)
parameter_counter[parameter.smirks] += 1
# write out parameter assignment data
out_json_path = os.path.join(forcefield.root, 'smirnoff_parameter_assignments.json')
with open(out_json_path, 'w') as jsonfile:
json.dump(parameter_assignment_data, jsonfile, indent=2)
logger.info("Force field assignment data written to %s\n" % out_json_path)
# print parameter coverages
logger.info("%4s %-100s %10s\n" % ("idx", "Parameter", "Count"))
logger.info("-"*118 + '\n')
n_covered = 0
for i,p in enumerate(forcefield.plist):
smirks = p.split('/')[-1]
logger.info('%4i %-100s : %10d\n' % (i, p, parameter_counter[smirks]))
if parameter_counter[smirks] > 0:
n_covered += 1
logger.info("SNIRNOFF Parameter Coverage Analysis result: %d/%d parameters are covered.\n" % (n_covered, len(forcefield.plist)))
logger.info("-"*118 + '\n')
def test_torsiondrive_index():
"""
Test generating an index using torsiondrive, this should tag the atoms in the torsion.
"""
mol = Molecule.from_file(get_data("methanol.sdf"))
mol.properties["atom_map"] = {4: 0, 0: 1, 1: 2, 5: 3}
factory = TorsiondriveDatasetFactory()
index = factory.create_index(mol)
tags = ["[C:2]", "[H:1]", "[O:3]", "[H:4]"]
for tag in tags:
assert tag in index
def filter_function(physical_property):
substance = physical_property.substance
for component in substance.components:
molecule = Molecule.from_smiles(component.smiles,
allow_undefined_stereo=True)
if not all([
x.element.symbol in allowed_elements
for x in molecule.atoms
]):
return False
return True
def from_directory(
cls: Type[T], directory: str, name: str, options: Dict[str, Any]
) -> T:
from openforcefield.topology import Molecule
input_molecule_path = os.path.join(directory, options["mol2"])
input_molecule = Molecule.from_file(
input_molecule_path, allow_undefined_stereo=True
)
return cls(
name=name,
molecule=input_molecule.to_smiles(explicit_hydrogens=False),
options=options,
)
def test_rmsd_filter():
"""
Test the RMSD conformer filter method.
"""
import copy
from simtk import unit
rmsd_filter = workflow_components.RMSDCutoffConformerFilter(cutoff=1)
mol = Molecule.from_smiles("CCCC")
# make a lot of conformers for the molecule
mol.generate_conformers(n_conformers=1000, rms_cutoff=0.5 * unit.angstrom, toolkit_registry=RDKitToolkitWrapper())
ref_mol = copy.deepcopy(mol)
result = rmsd_filter.apply([mol, ], processors=1)
# now make sure the number of conformers is different
assert result.molecules[0].n_conformers != ref_mol.n_conformers
def test_bespoke_target_torsion_smirks():
"""
Generate bespoke torsion smirks only for the target torsions and make sure the intended atoms are covered.
"""
gen = SmirksGenerator()
mol = Molecule.from_file(get_data("OCCO.sdf"))
torsion_smirks = gen._get_bespoke_torsion_smirks(molecule=mol,
central_bonds=[(1, 2)])
# there should be 3 unique smirks for this molecule
# H-C-C-H, H-C-C-O, O-C-C-O
assert len(torsion_smirks) == 3
for smirk in torsion_smirks:
atoms = condense_matches(mol.chemical_environment_matches(
smirk.smirks))
assert compare_matches(atoms, smirk.atoms) is True
def test_packmol_paracetamol():
from openforcefield.topology import Molecule
# Test something a bit more tricky than water
molecules = [Molecule.from_smiles("CC(=O)NC1=CC=C(C=C1)O")]
trajectory, _ = packmol.pack_box(molecules, [1],
box_size=([20] * 3) * unit.angstrom)
assert trajectory is not None
assert trajectory.n_chains == 1
assert trajectory.n_residues == 1
assert trajectory.n_atoms == 20
assert trajectory.topology.n_bonds == 20
def mol2_to_smiles(file_path):
"""Loads a receptor from a mol2 file.
Parameters
----------
file_path: str
The file path to the mol2 file.
Returns
-------
str
The smiles descriptor of the loaded receptor molecule
"""
receptor_molecule = Molecule.from_file(file_path, 'MOL2')
return receptor_molecule.to_smiles()
def test_generate_smirks(bespoke_smirks):
"""
Test the main worker method to gather bespoke and non bespoke terms.
"""
gen = SmirksGenerator()
gen.target_smirks = [
SmirksType.Vdw,
]
gen.generate_bespoke_terms = bespoke_smirks
mol = Molecule.from_smiles("CC")
smirks_list = gen.generate_smirks(molecule=mol)
# we only request one parameter type
types = set([smirk.type for smirk in smirks_list])
assert len(types) == 1
def min_ffxml(mol, ofs, ffxml):
"""
Minimize the mol with force field input from FFXML file.
Parameters
----------
mol : OpenEye single-conformer molecule
ofs : OpenEye output filestream
ffxml : string
name of FFXML file
"""
# make copy of the input mol
oe_mol = oechem.OEGraphMol(mol)
try:
# create openforcefield molecule ==> prone to triggering Exception
off_mol = Molecule.from_openeye(oe_mol)
# load in force field
ff = ForceField(ffxml)
# create components for OpenMM system
topology = Topology.from_molecules(molecules=[off_mol])
# create openmm system ==> prone to triggering Exception
#system = ff.create_openmm_system(topology, charge_from_molecules=[off_mol])
system = ff.create_openmm_system(topology)
except Exception as e:
smilabel = oechem.OEGetSDData(oe_mol, "SMILES QCArchive")
print( ' >>> openforcefield failed to create OpenMM system: '
f'{oe_mol.GetTitle()} {smilabel}: {e}')
return
positions = structure.extractPositionsFromOEMol(oe_mol)
# minimize structure with ffxml
newpos, energy = run_openmm(topology, system, positions)
# save geometry, save energy as tag, write mol to file
oe_mol.SetCoords(oechem.OEFloatArray(newpos))
oechem.OESetSDData(oe_mol, "Energy FFXML", str(energy))
oechem.OEWriteConstMolecule(ofs, oe_mol)
return
