def prepare_ga(dbfile='godb.db', N=20):
''' This method creates a database with the desired number
of randomly generated structures.
'''
blocks = [('Si', 7)] # the building blocks
l = [list(Atoms(block).numbers) * count for block, count in blocks]
stoichiometry = [int(item) for sublist in l for item in sublist]
atom_numbers = list(set(stoichiometry))
# This dictionary will be used to check that the shortest
# Si-Si distances are above a certain threshold
# (here 1.5 Angstrom):
blmin = {(14, 14): 1.5}
# This defines the cubic simulation cell:
slab = Atoms('', positions=np.zeros((0, 3)), cell=[16] * 3)
# This defines the smaller box in which the
# initial coordinates are allowed to vary
density = 0.12 # in atoms per cubic Angstrom
aspect_ratios = np.array([1.0, 1.0, 1.0])
v = len(stoichiometry) / density
l = np.cbrt(v / np.product(aspect_ratios))
cell = np.identity(3) * aspect_ratios * l
p0 = 0.5 * (np.diag(slab.get_cell() - cell))
box = [p0, cell]
# Seed the random number generators using the system time,
# to ensure that no two runs produce the same results:
np.random.seed()
seed()
# Generate the random structures and add them to the database:
sg = StartGenerator(slab=slab, atom_numbers=stoichiometry,
closest_allowed_distances=blmin,
box_to_place_in=box)
da = PrepareDB(db_file_name=dbfile,
simulation_cell=slab,
stoichiometry=stoichiometry)
for i in range(N):
a = sg.get_new_candidate()
da.add_unrelaxed_candidate(a)
return
def prepare_ga(dbfile='godb.db', N=20):
"""
This method creates a database with the desired number
of randomly generated structures.
"""
Z = atomic_numbers['Si']
atom_numbers = [Z] * 7
# This dictionary will be used to check that the shortest
# Si-Si distances are above a certain threshold
# (here 1.5 Angstrom):
blmin = {(Z, Z): 1.5}
# This defines the cubic simulation cell. In case there
big_cell = np.identity(3) * 16.
slab = Atoms('', cell=big_cell)
# This defines the smaller box in which the initial
# coordinates are allowed to be generated
density = 0.1 # in atoms per cubic Angstrom
L = np.cbrt(len(atom_numbers) / density)
small_cell = np.identity(3) * L
p0 = 0.5 * np.diag(big_cell - small_cell)
box = [p0, small_cell]
# Seed the random number generators using the system time,
# to ensure that no two runs produce the same results:
np.random.seed()
seed()
# Generate the random structures and add them to the database:
sg = StartGenerator(slab=slab, atom_numbers=atom_numbers,
closest_allowed_distances=blmin,
box_to_place_in=box)
da = PrepareDB(db_file_name=dbfile,
simulation_cell=slab,
stoichiometry=atom_numbers)
for i in range(N):
a = sg.get_new_candidate()
da.add_unrelaxed_candidate(a)
return
# (and not intramolecularly):
Z = atomic_numbers['N']
blmin = closest_distances_generator(atom_numbers=[Z],
ratio_of_covalent_radii=1.3)
# The bounds for the randomly generated unit cells:
cellbounds = CellBounds(bounds={'phi': [30, 150], 'chi': [30, 150],
'psi': [30, 150], 'a': [3, 50],
'b': [3, 50], 'c': [3, 50]})
# The familiar 'slab' object, here only providing
# the PBC as there are no atoms or cell vectors
# that need to be applied.
slab = Atoms('', pbc=True)
# create the starting population
sg = StartGenerator(slab, blocks, blmin, box_volume=box_volume,
cellbounds=cellbounds, splits=splits,
number_of_variable_cell_vectors=3,
test_too_far=False)
# Initialize the database
da = PrepareDB(db_file_name='gadb.db', simulation_cell=slab,
stoichiometry=[Z] * 16)
# Generate the new structures
# and add them to the database
for i in range(N):
a = sg.get_new_candidate()
da.add_unrelaxed_candidate(a)
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.
# Define the composition of the atoms to optimize
atom_numbers = 2 * [47] + 2 * [79]
# define the closest distance two atoms of a given species can be to each other
unique_atom_types = get_all_atom_types(slab, atom_numbers)
blmin = closest_distances_generator(atom_numbers=unique_atom_types,
ratio_of_covalent_radii=0.7)
# create the starting population
sg = StartGenerator(slab,
atom_numbers,
blmin,
box_to_place_in=[p0, [v1, v2, v3]])
# generate the starting population
population_size = 20
starting_population = [sg.get_new_candidate() for i in range(population_size)]
# from ase.visualize import view # uncomment these lines
# view(starting_population) # to see the starting population
# create the database to store information in
d = PrepareDB(db_file_name=db_file,
simulation_cell=slab,
stoichiometry=atom_numbers)
for a in starting_population:
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.
# Define the composition of the atoms to optimize
atom_numbers = 2 * [47] + 2 * [79]
# define the closest distance two atoms of a given species can be to each other
unique_atom_types = get_all_atom_types(slab, atom_numbers)
cd = closest_distances_generator(atom_numbers=unique_atom_types,
ratio_of_covalent_radii=0.7)
# create the starting population
sg = StartGenerator(slab=slab,
atom_numbers=atom_numbers,
closest_allowed_distances=cd,
box_to_place_in=[p0, [v1, v2, v3]])
# generate the starting population
population_size = 5
starting_population = [sg.get_new_candidate() for i in xrange(population_size)]
# from ase.visualize import view # uncomment these lines
# view(starting_population) # to see the starting population
# create the database to store information in
d = PrepareDB(db_file_name=db_file,
simulation_cell=slab,
stoichiometry=atom_numbers,)
# population_size=population_size)
def test_film_operators(seed):
from ase.ga.startgenerator import StartGenerator
from ase.ga.cutandsplicepairing import CutAndSplicePairing
from ase.ga.standardmutations import StrainMutation
from ase.ga.utilities import (closest_distances_generator, atoms_too_close,
CellBounds)
import numpy as np
from ase import Atoms
from ase.build import molecule
# set up the random number generator
rng = np.random.RandomState(seed)
slab = Atoms('', cell=(0, 0, 15), pbc=[True, True, False])
cation, anion = 'Mg', molecule('OH')
d_oh = anion.get_distance(0, 1)
blocks = [(cation, 4), (anion, 8)]
n_top = 4 + 8 * len(anion)
use_tags = True
num_vcv = 2
box_volume = 8. * n_top
blmin = closest_distances_generator(atom_numbers=[1, 8, 12],
ratio_of_covalent_radii=0.6)
cellbounds = CellBounds(
bounds={
'phi': [0.1 * 180., 0.9 * 180.],
'chi': [0.1 * 180., 0.9 * 180.],
'psi': [0.1 * 180., 0.9 * 180.],
'a': [2, 8],
'b': [2, 8]
})
box_to_place_in = [[None, None, 3.], [None, None, [0., 0., 5.]]]
sg = StartGenerator(slab,
blocks,
blmin,
box_volume=box_volume,
splits={(2, 1): 1},
box_to_place_in=box_to_place_in,
number_of_variable_cell_vectors=num_vcv,
cellbounds=cellbounds,
test_too_far=True,
test_dist_to_slab=False,
rng=rng)
parents = []
for i in range(2):
a = None
while a is None:
a = sg.get_new_candidate()
a.info['confid'] = i
parents.append(a)
assert len(a) == n_top
assert len(np.unique(a.get_tags())) == 4 + 8
assert np.allclose(a.get_pbc(), slab.get_pbc())
p = a.get_positions()
assert np.min(p[:, 2]) > 3. - 0.5 * d_oh
assert np.max(p[:, 2]) < 3. + 5. + 0.5 * d_oh
assert not atoms_too_close(a, blmin, use_tags=use_tags)
c = a.get_cell()
assert np.allclose(c[2], slab.get_cell()[2])
assert cellbounds.is_within_bounds(c)
v = a.get_volume() * 5. / 15.
assert abs(v - box_volume) < 1e-5
# Test cut-and-splice pairing and strain mutation
pairing = CutAndSplicePairing(slab,
n_top,
blmin,
number_of_variable_cell_vectors=num_vcv,
p1=1.,
p2=0.,
minfrac=0.15,
cellbounds=cellbounds,
use_tags=use_tags,
rng=rng)
strainmut = StrainMutation(blmin,
cellbounds=cellbounds,
number_of_variable_cell_vectors=num_vcv,
use_tags=use_tags,
rng=rng)
strainmut.update_scaling_volume(parents)
for operator in [pairing, strainmut]:
child = None
while child is None:
child, desc = operator.get_new_individual(parents)
assert not atoms_too_close(child, blmin, use_tags=use_tags)
cell = child.get_cell()
assert cellbounds.is_within_bounds(cell)
assert np.allclose(cell[2], slab.get_cell()[2])
def test_cutandsplicepairing(seed):
from ase.ga.startgenerator import StartGenerator
from ase.ga.utilities import closest_distances_generator, atoms_too_close
from ase.ga.cutandsplicepairing import CutAndSplicePairing
import numpy as np
from ase.build import fcc111
from ase.constraints import FixAtoms
# set up the random number generator
rng = np.random.RandomState(seed)
# first create two random starting candidates
slab = fcc111('Au', size=(4, 4, 2), vacuum=10.0, orthogonal=True)
slab.set_constraint(FixAtoms(mask=slab.positions[:, 2] <= 10.))
pos = slab.get_positions()
cell = slab.get_cell()
p0 = np.array([0., 0., max(pos[:, 2]) + 2.])
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.
blmin = closest_distances_generator(atom_numbers=[47, 79],
ratio_of_covalent_radii=0.7)
atom_numbers = 2 * [47] + 2 * [79]
sg = StartGenerator(slab=slab,
blocks=atom_numbers,
blmin=blmin,
box_to_place_in=[p0, [v1, v2, v3]],
rng=rng)
c1 = sg.get_new_candidate()
c1.info['confid'] = 1
c2 = sg.get_new_candidate()
c2.info['confid'] = 2
n_top = len(atom_numbers)
pairing = CutAndSplicePairing(slab, n_top, blmin, rng=rng)
c3, desc = pairing.get_new_individual([c1, c2])
# verify that the stoichiometry is preserved
assert np.all(c3.numbers == c1.numbers)
top1 = c1[-n_top:]
top2 = c2[-n_top:]
top3 = c3[-n_top:]
# verify that the positions in the new candidate come from c1 or c2
n1 = -1 * np.ones((n_top, ))
n2 = -1 * np.ones((n_top, ))
for i in range(n_top):
for j in range(n_top):
if np.allclose(top1.positions[j, :], top3.positions[i, :], 1e-12):
n1[i] = j
break
elif np.allclose(top2.positions[j, :], top3.positions[i, :],
1e-12):
n2[i] = j
break
assert (n1[i] > -1 and n2[i] == -1) or (n1[i] == -1 and n2[i] > -1)
# verify that c3 includes atoms from both c1 and c2
assert len(n1[n1 > -1]) > 0 and len(n2[n2 > -1]) > 0
# verify no atoms too close
assert not atoms_too_close(top3, blmin)
p0 = np.array([0., 0., max(pos[:, 2]) + 2.])
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.
# define the closest distance between two atoms of a given species
cd = closest_distances_generator(atom_numbers=[47, 79],
ratio_of_covalent_radii=0.7)
# Define the composition of the atoms to optimize
atom_numbers = 2 * [47] + 2 * [79]
# create the starting population
sg = StartGenerator(slab=slab,
atom_numbers=atom_numbers,
closest_allowed_distances=cd,
box_to_place_in=[p0, [v1, v2, v3]])
# generate the starting population
starting_population = [sg.get_new_candidate() for i in range(20)]
d = PrepareDB(db_file_name=db_file,
simulation_cell=slab,
stoichiometry=atom_numbers)
for a in starting_population:
d.add_unrelaxed_candidate(a)
# and now for the actual test
dc = DataConnection(db_file)
def test_mutations(seed):
from ase.ga.startgenerator import StartGenerator
from ase.ga.utilities import closest_distances_generator
from ase.ga.standardmutations import RattleMutation, PermutationMutation
import numpy as np
from ase.build import fcc111
from ase.constraints import FixAtoms
# set up the random number generator
rng = np.random.RandomState(seed)
# first create two random starting candidates
slab = fcc111('Au', size=(4, 4, 2), vacuum=10.0, orthogonal=True)
slab.set_constraint(FixAtoms(mask=slab.positions[:, 2] <= 10.))
pos = slab.get_positions()
cell = slab.get_cell()
p0 = np.array([0., 0., max(pos[:, 2]) + 2.])
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.
blmin = closest_distances_generator(atom_numbers=[47, 79],
ratio_of_covalent_radii=0.7)
atom_numbers = 2 * [47] + 2 * [79]
n_top = len(atom_numbers)
sg = StartGenerator(slab=slab,
blocks=atom_numbers,
blmin=blmin,
box_to_place_in=[p0, [v1, v2, v3]],
rng=rng)
c1 = sg.get_new_candidate()
c1.info['confid'] = 1
# first verify that the rattle mutation works
rmut = RattleMutation(blmin, n_top, rattle_strength=0.8, rattle_prop=0.4,
rng=rng)
c2, desc = rmut.get_new_individual([c1])
assert np.all(c1.numbers == c2.numbers)
top1 = c1[-n_top:]
top2 = c2[-n_top:]
slab2 = c2[0:(len(c1) - n_top)]
assert len(slab) == len(slab2)
assert np.all(slab.get_positions() == slab2.get_positions())
dp = np.sum((top2.get_positions() - top1.get_positions())**2, axis=1)**0.5
# check that all displacements are smaller than the rattle strength we
# cannot check if 40 % of the structures have been rattled since it is
# probabilistic and because the probability will be lower if two atoms
# get too close
for p in dp:
assert p < 0.8 * 3**0.5
# now we check the permutation mutation
mmut = PermutationMutation(n_top, probability=0.5, rng=rng)
c3, desc = mmut.get_new_individual([c1])
assert np.all(c1.numbers == c3.numbers)
top1 = c1[-n_top:]
top2 = c3[-n_top:]
slab2 = c3[0:(len(c1) - n_top)]
assert len(slab) == len(slab2)
assert np.all(slab.get_positions() == slab2.get_positions())
dp = np.sum((top2.get_positions() - top1.get_positions())**2, axis=1)**0.5
# verify that two positions have been changed
assert len(dp[dp > 0]) == 2
slab.set_constraint(FixAtoms(mask=slab.positions[:, 2] <= 10.0))
pos = slab.get_positions()
cell = slab.get_cell()
p0 = np.array([0.0, 0.0, max(pos[:, 2]) + 2.0])
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.0
cd = closest_distances_generator(atom_numbers=[47, 79], ratio_of_covalent_radii=0.7)
atom_numbers = 2 * [47] + 2 * [79]
sg = StartGenerator(
slab=slab, atom_numbers=atom_numbers, closest_allowed_distances=cd, box_to_place_in=[p0, [v1, v2, v3]]
)
c1 = sg.get_new_candidate()
c1.info["confid"] = 1
c2 = sg.get_new_candidate()
c2.info["confid"] = 2
n_top = len(atom_numbers)
pairing = CutAndSplicePairing(slab, n_top, cd)
c3, desc = pairing.get_new_individual([c1, c2])
# verify that the stoichiometry is preserved
assert np.all(c3.numbers == c1.numbers)
# controls the level of translational symmetry (within the unit
# cell) of the randomly generated structures. Here a 1:1 ratio
# of splitting factors 2 and 1 is used:
splits = {(2,): 1, (1,): 1}
# There will hence be a 50% probability that a candidate
# is constructed by repeating an randomly generated Ag12
# structure along a randomly chosen axis. In the other 50%
# of cases, no cell cell splitting will be applied.
# The 'slab' object in the GA serves as a template
# in the creation of new structures, which inherit
# the slab's atomic positions (if any), cell vectors
# (if specified), and periodic boundary conditions.
# Here only the last property is relevant:
slab = Atoms('', pbc=True)
# Initialize the random structure generator
sg = StartGenerator(slab, blocks, blmin, box_volume=volume,
number_of_variable_cell_vectors=3,
cellbounds=cellbounds, splits=splits)
# Create the database
da = PrepareDB(db_file_name='gadb.db',
stoichiometry=[Z] * 24)
# Generate N random structures
# and add them to the database
for i in range(N):
a = sg.get_new_candidate()
da.add_unrelaxed_candidate(a)
pos = slab.get_positions()
cell = slab.get_cell()
p0 = np.array([0., 0., max(pos[:, 2]) + 2.])
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.
cd = closest_distances_generator(atom_numbers=[47, 79],
ratio_of_covalent_radii=0.7)
atom_numbers = 2 * [47] + 2 * [79]
sg = StartGenerator(slab=slab,
atom_numbers=atom_numbers,
closest_allowed_distances=cd,
box_to_place_in=[p0, [v1, v2, v3]])
c1 = sg.get_new_candidate()
c1.info['confid'] = 1
c2 = sg.get_new_candidate()
c2.info['confid'] = 2
n_top = len(atom_numbers)
pairing = CutAndSplicePairing(slab, n_top, cd)
c3, desc = pairing.get_new_individual([c1, c2])
# verify that the stoichiometry is preserved
assert np.all(c3.numbers == c1.numbers)
def test_basic_example_main_run(seed, testdir):
# set up the random number generator
rng = np.random.RandomState(seed)
# create the surface
slab = fcc111('Au', size=(4, 4, 1), vacuum=10.0, orthogonal=True)
slab.set_constraint(FixAtoms(mask=len(slab) * [True]))
# define the volume in which the adsorbed cluster is optimized
# the volume is defined by a corner position (p0)
# and three spanning vectors (v1, v2, v3)
pos = slab.get_positions()
cell = slab.get_cell()
p0 = np.array([0., 0., max(pos[:, 2]) + 2.])
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.
# Define the composition of the atoms to optimize
atom_numbers = 2 * [47] + 2 * [79]
# define the closest distance two atoms of a given species can be to each other
unique_atom_types = get_all_atom_types(slab, atom_numbers)
blmin = closest_distances_generator(atom_numbers=unique_atom_types,
ratio_of_covalent_radii=0.7)
# create the starting population
sg = StartGenerator(slab=slab,
blocks=atom_numbers,
blmin=blmin,
box_to_place_in=[p0, [v1, v2, v3]],
rng=rng)
# generate the starting population
population_size = 5
starting_population = [sg.get_new_candidate() for i in range(population_size)]
# from ase.visualize import view # uncomment these lines
# view(starting_population) # to see the starting population
# create the database to store information in
d = PrepareDB(db_file_name=db_file,
simulation_cell=slab,
stoichiometry=atom_numbers)
for a in starting_population:
d.add_unrelaxed_candidate(a)
# XXXXXXXXXX This should be the beginning of a new test,
# but we are using some resources from the precious part.
# Maybe refactor those things as (module-level?) fixtures.
# Change the following three parameters to suit your needs
population_size = 5
mutation_probability = 0.3
n_to_test = 5
# Initialize the different components of the GA
da = DataConnection('gadb.db')
atom_numbers_to_optimize = da.get_atom_numbers_to_optimize()
n_to_optimize = len(atom_numbers_to_optimize)
slab = da.get_slab()
all_atom_types = get_all_atom_types(slab, atom_numbers_to_optimize)
blmin = closest_distances_generator(all_atom_types,
ratio_of_covalent_radii=0.7)
comp = InteratomicDistanceComparator(n_top=n_to_optimize,
pair_cor_cum_diff=0.015,
pair_cor_max=0.7,
dE=0.02,
mic=False)
pairing = CutAndSplicePairing(slab, n_to_optimize, blmin, rng=rng)
mutations = OperationSelector([1., 1., 1.],
[MirrorMutation(blmin, n_to_optimize, rng=rng),
RattleMutation(blmin, n_to_optimize, rng=rng),
PermutationMutation(n_to_optimize, rng=rng)],
rng=rng)
# Relax all unrelaxed structures (e.g. the starting population)
while da.get_number_of_unrelaxed_candidates() > 0:
a = da.get_an_unrelaxed_candidate()
a.calc = EMT()
print('Relaxing starting candidate {0}'.format(a.info['confid']))
dyn = BFGS(a, trajectory=None, logfile=None)
dyn.run(fmax=0.05, steps=100)
set_raw_score(a, -a.get_potential_energy())
da.add_relaxed_step(a)
# create the population
population = Population(data_connection=da,
population_size=population_size,
comparator=comp,
rng=rng)
# test n_to_test new candidates
for i in range(n_to_test):
print('Now starting configuration number {0}'.format(i))
a1, a2 = population.get_two_candidates()
a3, desc = pairing.get_new_individual([a1, a2])
if a3 is None:
continue
da.add_unrelaxed_candidate(a3, description=desc)
# Check if we want to do a mutation
if rng.rand() < mutation_probability:
a3_mut, desc = mutations.get_new_individual([a3])
if a3_mut is not None:
da.add_unrelaxed_step(a3_mut, desc)
a3 = a3_mut
# Relax the new candidate
a3.calc = EMT()
dyn = BFGS(a3, trajectory=None, logfile=None)
dyn.run(fmax=0.05, steps=100)
set_raw_score(a3, -a3.get_potential_energy())
da.add_relaxed_step(a3)
population.update()
write('all_candidates.traj', da.get_all_relaxed_candidates())
def test_chain_operators(seed):
from ase.ga.startgenerator import StartGenerator
from ase.ga.cutandsplicepairing import CutAndSplicePairing
from ase.ga.standardmutations import StrainMutation
from ase.ga.utilities import (closest_distances_generator, atoms_too_close,
CellBounds)
import numpy as np
from ase import Atoms
# set up the random number generator
rng = np.random.RandomState(seed)
slab = Atoms('', cell=(0, 16, 16), pbc=[True, False, False])
blocks = ['C'] * 8
n_top = 8
use_tags = False
num_vcv = 1
box_volume = 8. * n_top
blmin = closest_distances_generator(atom_numbers=[6],
ratio_of_covalent_radii=0.6)
cellbounds = CellBounds(
bounds={
'phi': [0.1 * 180., 0.9 * 180.],
'chi': [0.1 * 180., 0.9 * 180.],
'psi': [0.1 * 180., 0.9 * 180.],
'a': [1, 6]
})
box_to_place_in = [[None, 6., 6.], [None, [0., 4., 0.], [0., 0., 4.]]]
sg = StartGenerator(slab,
blocks,
blmin,
box_volume=box_volume,
splits=None,
box_to_place_in=box_to_place_in,
number_of_variable_cell_vectors=num_vcv,
cellbounds=cellbounds,
test_too_far=True,
test_dist_to_slab=False,
rng=rng)
parents = []
for i in range(2):
a = None
while a is None:
a = sg.get_new_candidate()
a.info['confid'] = i
parents.append(a)
assert len(a) == n_top
assert len(np.unique(a.get_tags())) == 8
assert np.allclose(a.get_pbc(), slab.get_pbc())
p = a.get_positions()
assert np.min(p[:, 1:]) > 6.
assert np.max(p[:, 1:]) < 6. + 4.
assert not atoms_too_close(a, blmin, use_tags=use_tags)
c = a.get_cell()
assert np.allclose(c[1:], slab.get_cell()[1:])
assert cellbounds.is_within_bounds(c)
v = a.get_volume() * (4. / 16.)**2
assert abs(v - box_volume) < 1e-5
# Test cut-and-splice pairing and strain mutation
pairing = CutAndSplicePairing(slab,
n_top,
blmin,
number_of_variable_cell_vectors=num_vcv,
p1=1.,
p2=0.,
minfrac=0.15,
cellbounds=cellbounds,
use_tags=use_tags,
rng=rng)
strainmut = StrainMutation(blmin,
cellbounds=cellbounds,
number_of_variable_cell_vectors=num_vcv,
use_tags=use_tags,
rng=rng)
strainmut.update_scaling_volume(parents)
for operator in [pairing, strainmut]:
child = None
while child is None:
child, desc = operator.get_new_individual(parents)
assert not atoms_too_close(child, blmin, use_tags=use_tags)
cell = child.get_cell()
assert cellbounds.is_within_bounds(cell)
assert np.allclose(cell[1:], slab.get_cell()[1:])
c = slab.get_cell()
v1 = np.array((c[0][0], 0., 0.))
v2 = np.array((0., c[1][1], 0.))
v3 = np.array((0., 0., 6.))
p0 = np.array((0., 0., 8.))
box = [p0, [v1, v2, v3]]
stoichiometry = 5 * [22] + 10 * [8]
print 'slab', buildFeature(slab, 6, [8, 22])
dmin = closest_distances_generator(atom_numbers=[22, 8],
ratio_of_covalent_radii=0.6)
sg = StartGenerator(
slab=slab, # Generator to generate initial structures
atom_numbers=stoichiometry,
closest_allowed_distances=dmin,
box_to_place_in=box)
calc = MorsePotential()
test = sg.get_new_candidate()
test.set_calculator(calc)
test.info['confid'] = 1
view(test)
cd = ClusterDistanceMutation(slab,
len(stoichiometry),
dmin,
5,
1,
verbose=True)
def test_database_logic(seed, testdir):
from ase.ga.data import PrepareDB
from ase.ga.data import DataConnection
from ase.ga.startgenerator import StartGenerator
from ase.ga.utilities import closest_distances_generator
from ase.ga import set_raw_score
import numpy as np
from ase.build import fcc111
from ase.constraints import FixAtoms
# set up the random number generator
rng = np.random.RandomState(seed)
slab = fcc111('Au', size=(4, 4, 2), vacuum=10.0, orthogonal=True)
slab.set_constraint(FixAtoms(mask=slab.positions[:, 2] <= 10.))
# define the volume in which the adsorbed cluster is optimized
# the volume is defined by a corner position (p0)
# and three spanning vectors (v1, v2, v3)
pos = slab.get_positions()
cell = slab.get_cell()
p0 = np.array([0., 0., max(pos[:, 2]) + 2.])
v1 = cell[0, :] * 0.8
v2 = cell[1, :] * 0.8
v3 = cell[2, :]
v3[2] = 3.
# define the closest distance between two atoms of a given species
blmin = closest_distances_generator(atom_numbers=[47, 79],
ratio_of_covalent_radii=0.7)
# Define the composition of the atoms to optimize
atom_numbers = 2 * [47] + 2 * [79]
# create the starting population
sg = StartGenerator(slab=slab,
blocks=atom_numbers,
blmin=blmin,
box_to_place_in=[p0, [v1, v2, v3]],
rng=rng)
# generate the starting population
starting_population = [sg.get_new_candidate() for i in range(20)]
d = PrepareDB(db_file_name=db_file,
simulation_cell=slab,
stoichiometry=atom_numbers)
for a in starting_population:
d.add_unrelaxed_candidate(a)
# and now for the actual test
dc = DataConnection(db_file)
dc.get_slab()
dc.get_atom_numbers_to_optimize()
assert dc.get_number_of_unrelaxed_candidates() == 20
a1 = dc.get_an_unrelaxed_candidate()
dc.mark_as_queued(a1)
assert dc.get_number_of_unrelaxed_candidates() == 19
assert len(dc.get_all_candidates_in_queue()) == 1
set_raw_score(a1, 0.0)
dc.add_relaxed_step(a1)
assert dc.get_number_of_unrelaxed_candidates() == 19
assert len(dc.get_all_candidates_in_queue()) == 0
assert len(dc.get_all_relaxed_candidates()) == 1
a2 = dc.get_an_unrelaxed_candidate()
dc.mark_as_queued(a2)
confid = a2.info['confid']
assert dc.get_all_candidates_in_queue()[0] == confid
dc.remove_from_queue(confid)
assert len(dc.get_all_candidates_in_queue()) == 0
def test_bulk_operators(seed):
# set up the random number generator
rng = np.random.RandomState(seed)
h2 = Atoms('H2', positions=[[0, 0, 0], [0, 0, 0.75]])
blocks = [('H', 4), ('H2O', 3), (h2, 2)] # the building blocks
volume = 40. * sum([x[1] for x in blocks]) # cell volume in angstrom^3
splits = {(2,): 1, (1,): 1} # cell splitting scheme
stoichiometry = []
for block, count in blocks:
if type(block) == str:
stoichiometry += list(Atoms(block).numbers) * count
else:
stoichiometry += list(block.numbers) * count
atom_numbers = list(set(stoichiometry))
blmin = closest_distances_generator(atom_numbers=atom_numbers,
ratio_of_covalent_radii=1.3)
cellbounds = CellBounds(bounds={'phi': [30, 150], 'chi': [30, 150],
'psi': [30, 150], 'a': [3, 50],
'b': [3, 50], 'c': [3, 50]})
slab = Atoms('', pbc=True)
sg = StartGenerator(slab, blocks, blmin, box_volume=volume,
number_of_variable_cell_vectors=3,
cellbounds=cellbounds, splits=splits, rng=rng)
# Generate 2 candidates
a1 = sg.get_new_candidate()
a1.info['confid'] = 1
a2 = sg.get_new_candidate()
a2.info['confid'] = 2
# Define and test genetic operators
n_top = len(a1)
pairing = CutAndSplicePairing(slab, n_top, blmin, p1=1., p2=0., minfrac=0.15,
number_of_variable_cell_vectors=3,
cellbounds=cellbounds, use_tags=True, rng=rng)
a3, desc = pairing.get_new_individual([a1, a2])
cell = a3.get_cell()
assert cellbounds.is_within_bounds(cell)
assert not atoms_too_close(a3, blmin, use_tags=True)
n_top = len(a1)
strainmut = StrainMutation(blmin, stddev=0.7, cellbounds=cellbounds,
number_of_variable_cell_vectors=3,
use_tags=True, rng=rng)
softmut = SoftMutation(blmin, bounds=[2., 5.], used_modes_file=None,
use_tags=True) # no rng
rotmut = RotationalMutation(blmin, fraction=0.3, min_angle=0.5 * np.pi,
rng=rng)
rattlemut = RattleMutation(blmin, n_top, rattle_prop=0.3, rattle_strength=0.5,
use_tags=True, test_dist_to_slab=False, rng=rng)
rattlerotmut = RattleRotationalMutation(rattlemut, rotmut) # no rng
permut = PermutationMutation(n_top, probability=0.33, test_dist_to_slab=False,
use_tags=True, blmin=blmin, rng=rng)
combmut = CombinationMutation(rattlemut, rotmut, verbose=True) # no rng
mutations = [strainmut, softmut, rotmut,
rattlemut, rattlerotmut, permut, combmut]
for i, mut in enumerate(mutations):
a = [a1, a2][i % 2]
a3 = None
while a3 is None:
a3, desc = mut.get_new_individual([a])
cell = a3.get_cell()
assert cellbounds.is_within_bounds(cell)
assert np.all(a3.numbers == a.numbers)
assert not atoms_too_close(a3, blmin, use_tags=True)
modes_file = 'modes.txt'
softmut_with = SoftMutation(blmin, bounds=[2., 5.], use_tags=True,
used_modes_file=modes_file) # no rng
no_muts = 3
for _ in range(no_muts):
softmut_with.get_new_individual([a1])
softmut_with.read_used_modes(modes_file)
assert len(list(softmut_with.used_modes.values())[0]) == no_muts
os.remove(modes_file)
comparator = OFPComparator(recalculate=True)
gold = bulk('Au') * (2, 2, 2)
assert comparator.looks_like(gold, gold)
# This move should not exceed the default threshold
gc = gold.copy()
gc[0].x += .1
assert comparator.looks_like(gold, gc)
# An additional step will exceed the threshold
gc[0].x += .2
assert not comparator.looks_like(gold, gc)