示例#1
0
def run_ga(n_to_test, kptdensity=3.5):
    population_size = 20
    da = DataConnection('godb.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, 0.05)  # 0.5

    # defining genetic operators:
    mutation_probability = 0.75
    pairing = CutAndSplicePairing(blmin,
                                  p1=1.,
                                  p2=0.,
                                  minfrac=0.15,
                                  use_tags=False)
    cellbounds = CellBounds(
        bounds={
            'phi': [0.2 * 180., 0.8 * 180.],
            'chi': [0.2 * 180., 0.8 * 180.],
            'psi': [0.2 * 180., 0.8 * 180.]
        })
    strainmut = StrainMutation(blmin,
                               stddev=0.7,
                               cellbounds=cellbounds,
                               use_tags=False)
    blmin_soft = closest_distances_generator(all_atom_types, 0.1)
    softmut = SoftMutation(blmin_soft, bounds=[2., 5.], use_tags=False)
    rattlemut = RattleMutation(blmin,
                               n_to_optimize,
                               rattle_prop=0.8,
                               rattle_strength=2.5,
                               use_tags=False)
    mutations = OperationSelector([4., 4., 2], [softmut, strainmut, rattlemut])

    if True:
        # recalculate raw scores
        structures = da.get_all_relaxed_candidates()
        for atoms in structures:
            atoms = singlepoint(atoms, kptdensity=kptdensity)
            da.c.delete([atoms.info['relax_id']])
            if 'data' not in atoms.info:
                atoms.info['data'] = {}
            da.add_relaxed_step(atoms)
        print('Finished recalculating raw scores')

    # relaxing the initial candidates:
    while da.get_number_of_unrelaxed_candidates() > 0:
        a = da.get_an_unrelaxed_candidate()
        a.wrap()
        a = relax_one(a, kptdensity=kptdensity)
        da.add_relaxed_step(a)

    # create the population
    population = Population(data_connection=da,
                            population_size=population_size,
                            comparator=comparator,
                            logfile='log.txt')

    current_pop = population.get_current_population()
    strainmut.update_scaling_volume(current_pop, w_adapt=0.5, n_adapt=4)
    pairing.update_scaling_volume(current_pop, w_adapt=0.5, n_adapt=4)

    # Test n_to_test new candidates
    ga_raw_scores = []
    step = 0
    for step in range(n_to_test):
        print('Starting configuration number %d' % step, flush=True)

        clock = time()
        a3 = None
        r = random()
        if r > mutation_probability:
            while a3 is None:
                a1, a2 = population.get_two_candidates()
                a3, desc = pairing.get_new_individual([a1, a2])
        else:
            while a3 is None:
                a1 = population.get_one_candidate()
                a3, desc = mutations.get_new_individual([a1])

        dt = time() - clock
        op = 'pairing' if r > mutation_probability else 'mutating'
        print('Time for %s candidate(s): %.3f' % (op, dt), flush=True)

        a3.wrap()
        da.add_unrelaxed_candidate(a3, description=desc)

        a3 = relax_one(a3, kptdensity=kptdensity)
        da.add_relaxed_step(a3)

        # Various updates:
        population.update()
        current_pop = population.get_current_population()

        if step % 10 == 0:
            strainmut.update_scaling_volume(current_pop,
                                            w_adapt=0.5,
                                            n_adapt=4)
            pairing.update_scaling_volume(current_pop, w_adapt=0.5, n_adapt=4)
            write('current_population.traj', current_pop)

        # Print out information for easy analysis/plotting afterwards:
        if r > mutation_probability:
            print('Step %d %s %.3f %.3f %.3f' % (step, desc,\
                   get_raw_score(a1), get_raw_score(a2), get_raw_score(a3)))
        else:
            print('Step %d %s %.3f %.3f' % (step, desc,\
                   get_raw_score(a1), get_raw_score(a3)))

        print('Step %d highest raw score in pop: %.3f' % \
              (step, get_raw_score(current_pop[0])))
        ga_raw_scores.append(get_raw_score(a3))
        print('Step %d highest raw score generated by GA: %.3f' % \
              (step, max(ga_raw_scores)))

    emin = population.pop[0].get_potential_energy()
    print('GA finished after step %d' % step)
    print('Lowest energy = %8.3f eV' % emin, flush=True)
    write('all_candidates.traj', da.get_all_relaxed_candidates())
    write('current_population.traj', population.get_current_population())
示例#2
0
def run_ga(n_to_test, kptdensity=None):
    ''' This method specifies how to run the GA once the
    initial random structures have been stored in godb.db.
    '''
    # Various initializations:
    population_size = 10
    da = DataConnection('godb.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=0.05)

    # Defining the mix of genetic operators:
    mutation_probability = 0.3333
    pairing = CutAndSplicePairing(slab, n_to_optimize, blmin)
    rattlemut = RattleMutation(blmin, n_to_optimize,
                               rattle_prop=0.8, rattle_strength=1.5)
    mirrormut = MirrorMutation(blmin, n_to_optimize)
    mutations = OperationSelector([1., 1.], [rattlemut, mirrormut])

    if True:
        # Recalculate raw scores of any relaxed candidates
        # present in the godb.db database (only applies to 
        # iter007).
        structures = da.get_all_relaxed_candidates()
        for atoms in structures:
            atoms = singlepoint(atoms)
            da.c.delete([atoms.info['relax_id']])
            if 'data' not in atoms.info:
                atoms.info['data'] = {}
            da.add_relaxed_step(atoms)
        print('Finished recalculating raw scores')

    # Relax the randomly generated initial candidates:
    while da.get_number_of_unrelaxed_candidates() > 0:
        a = da.get_an_unrelaxed_candidate()
        a.wrap()
        a = relax_one(a)
        da.add_relaxed_step(a)

    # Create the population
    population = Population(data_connection=da,
                            population_size=population_size,
                            comparator=comparator,
                            logfile='log.txt')
    current_pop = population.get_current_population()

    # Test n_to_test new candidates
    ga_raw_scores = []
    step = 0
    for step in range(n_to_test):
        print('Starting configuration number %d' % step, flush=True)

        clock = time()
        a3 = None
        r = random()
        if r > mutation_probability:
            while a3 is None:
                a1, a2 = population.get_two_candidates()
                a3, desc = pairing.get_new_individual([a1, a2])
        else:
            while a3 is None:
                a1 = population.get_one_candidate()
                a3, desc = mutations.get_new_individual([a1])

        dt = time() - clock
        op = 'pairing' if r > mutation_probability else 'mutating'
        print('Time for %s candidate(s): %.3f' % (op, dt), flush=True)

        a3.wrap()
        da.add_unrelaxed_candidate(a3, description=desc)

        a3 = relax_one(a3)
        da.add_relaxed_step(a3)

        # Various updates:
        population.update()
        current_pop = population.get_current_population()
        write('current_population.traj', current_pop)

        # Print out information for easy analysis/plotting afterwards:
        if r > mutation_probability:
            print('Step %d %s %.3f %.3f %.3f' % (step, desc,\
                   get_raw_score(a1), get_raw_score(a2), get_raw_score(a3)))
        else:
            print('Step %d %s %.3f %.3f' % (step, desc,\
                   get_raw_score(a1), get_raw_score(a3)))

        print('Step %d highest raw score in pop: %.3f' % \
              (step, get_raw_score(current_pop[0])))
        ga_raw_scores.append(get_raw_score(a3))
        print('Step %d highest raw score generated by GA: %.3f' % \
              (step, max(ga_raw_scores)))

    emin = population.pop[0].get_potential_energy()
    print('GA finished after step %d' % step)
    print('Lowest energy = %8.3f eV' % emin, flush=True)
    write('all_candidates.traj', da.get_all_relaxed_candidates())
    write('current_population.traj', population.get_current_population())