def __init__(self,
natoms,
minimiser,
composition="default",
labels=("X", ),
pop_size=10,
max_generation=10,
selector=TournamentSelector(3),
offspring=8,
mutant_rate=0.1,
remove_duplicates=False,
mutator=MutateReplace(),
crossover=DeavenHo()):
#Parameters
self.max_generation = max_generation
self.mutant_rate = mutant_rate
self.offspring = offspring
self.pop_size = pop_size
self.remove_duplicates = remove_duplicates
self.selector = selector
self.mutator = mutator
self.crossover = crossover
#Factory
self.factory = ClusterFactory(natoms, minimiser, composition, labels)
#PopulationList
self.population = PopulationList(natoms, self.factory, pop_size)
#Evolutionary progress
self.mean_energy_series = []
self.min_energy_series = []
self.db = Database(db="mydatabase.sqlite")
self.storage = self.db.minimum_adder()
def setUp(self):
natoms = 10
minimiser = PeleMinimiser(lj.LJ())
factory = ClusterFactory(natoms, minimiser)
self.population = PopulationList(natoms, factory, max_size=5)
while len(self.population) < self.population.max_size:
self.population.append(factory.get_random_cluster())
def test_population(self):
natoms=3
minimiser=PeleMinimiser(LJCluster(natoms))
factory=ClusterFactory(natoms,minimiser)
with open("restart.xyz",'r') as xyz_file:
population=PopulationList(natoms,factory)
population.read_xyz(xyz_file)
self.assertEquals(-5.,population[0].get_energy())
self.assertEquals(-4.,population[1].get_energy())
def test_population(self):
natoms = 3
minimiser = PeleMinimiser(LJCluster(natoms))
factory = ClusterFactory(natoms, minimiser)
with open("restart.xyz", "r") as xyz_file:
population = PopulationList(natoms, factory)
population.read_xyz(xyz_file)
self.assertEquals(-5.0, population[0].get_energy())
self.assertEquals(-4.0, population[1].get_energy())
def __init__(self,natoms,minimiser,
composition="default",labels=("X",),
pop_size=10,max_generation=10,
selector=TournamentSelector(3),
offspring=8,mutant_rate=0.1,remove_duplicates=False,
mutator=MutateReplace(),
crossover=DeavenHo()):
#Parameters
self.max_generation = max_generation
self.mutant_rate = mutant_rate
self.offspring=offspring
self.pop_size=pop_size
self.remove_duplicates=remove_duplicates
self.selector=selector
self.mutator = mutator
self.crossover = crossover
#Factory
self.factory=ClusterFactory(natoms,minimiser,composition,labels)
#PopulationList
self.population = PopulationList(natoms,self.factory,pop_size)
#Evolutionary progress
self.mean_energy_series=[]
self.min_energy_series=[]
self.db = Database(db="mydatabase.sqlite")
self.storage = self.db.minimum_adder()
def setUp(self):
natoms=10
minimiser=PeleMinimiser(lj.LJ())
factory=ClusterFactory(natoms,minimiser)
self.population=PopulationList(natoms,factory,max_size=5)
while len(self.population) < self.population.max_size:
self.population.append(factory.get_random_cluster())
def __init__(self,
natoms,
minimiser,
composition="default",
labels=("X", ),
pop_size=10,
max_generation=10,
selector=TournamentSelector(3),
offspring=8,
mutant_rate=0.1,
remove_duplicates=False,
mass_extinction=False,
epoch_thresh=1.e-6,
restart=False,
mutator=MutateReplace(),
crossover=DeavenHo()):
#Parameters
self.max_generation = max_generation
self.mutant_rate = mutant_rate
self.offspring = offspring
self.pop_size = pop_size
self.remove_duplicates = remove_duplicates
self.mass_extinction = mass_extinction
self.epoch_thresh = epoch_thresh
self.selector = selector
self.mutator = mutator
self.crossover = crossover
#Factory
self.factory = ClusterFactory(natoms, minimiser, composition, labels)
#PopulationList
self.population = PopulationList(natoms, self.factory, pop_size)
if restart is False:
while len(self.population) < self.population.max_size:
self.population.append(self.factory.get_random_cluster())
self.population.sort_energy()
else:
with open("restart.xyz", 'r') as xyz_file:
self.population.read_xyz(xyz_file)
#Evolutionary progress
self.mean_energy_series = []
self.mean_energy_series.append(self.population.get_mean_energy())
self.min_energy_series = []
self.min_energy_series.append(self.population.get_lowest_energy())
class ClusterTest(unittest.TestCase):
def setUp(self):
natoms = 10
minimiser = PeleMinimiser(lj.LJ())
factory = ClusterFactory(natoms, minimiser)
self.population = PopulationList(natoms, factory, max_size=5)
while len(self.population) < self.population.max_size:
self.population.append(factory.get_random_cluster())
self.population.sort_energy()
def test_tournament(self):
selector = TournamentSelector(3)
pair = selector.select(self.population)
self.assertEquals(len(pair), 2)
self.assertNotEqual(pair[0], pair[1])
def test_roulette(self):
selector = RouletteSelector()
for _ in range(0, 50): # Repeat for several random selections
pair = selector.select(self.population)
self.assertEquals(len(pair), 2)
self.assertNotEqual(pair[0], pair[1])
class ClusterTest(unittest.TestCase):
def setUp(self):
natoms = 10
minimiser = PeleMinimiser(lj.LJ())
factory = ClusterFactory(natoms, minimiser)
self.population = PopulationList(natoms, factory, max_size=5)
while len(self.population) < self.population.max_size:
self.population.append(factory.get_random_cluster())
self.population.sort_energy()
def test_tournament(self):
selector = TournamentSelector(3)
pair = selector.select(self.population)
self.assertEquals(len(pair), 2)
self.assertNotEqual(pair[0], pair[1])
def test_roulette(self):
selector = RouletteSelector()
for _ in range(0, 50): #Repeat for several random selections
pair = selector.select(self.population)
self.assertEquals(len(pair), 2)
self.assertNotEqual(pair[0], pair[1])
class ClusterTest(unittest.TestCase):
def setUp(self):
natoms=10
minimiser=PeleMinimiser(lj.LJ())
factory=ClusterFactory(natoms,minimiser)
self.population=PopulationList(natoms,factory,max_size=5)
while len(self.population) < self.population.max_size:
self.population.append(factory.get_random_cluster())
def test_energy_sort(self):
self.population.sort_energy()
for i in range(1,self.population.max_size):
self.assertGreater(self.population.get_energy(i),
self.population.get_energy(i-1))
class ClusterTest(unittest.TestCase):
def setUp(self):
natoms = 10
minimiser = PeleMinimiser(lj.LJ())
factory = ClusterFactory(natoms, minimiser)
self.population = PopulationList(natoms, factory, max_size=5)
while len(self.population) < self.population.max_size:
self.population.append(factory.get_random_cluster())
def test_energy_sort(self):
self.population.sort_energy()
for i in range(1, self.population.max_size):
self.assertGreater(self.population.get_energy(i),
self.population.get_energy(i - 1))
def __init__(self,natoms,minimiser,
composition="default",labels=("X",),
pop_size=10,max_generation=10,
selector=TournamentSelector(3),
offspring=8,mutant_rate=0.1,remove_duplicates=False,
mass_extinction=False,epoch_thresh=1.e-6,
restart=False,
mutator=MutateReplace(),
crossover=DeavenHo()):
#Parameters
self.max_generation = max_generation
self.mutant_rate = mutant_rate
self.offspring=offspring
self.pop_size=pop_size
self.remove_duplicates=remove_duplicates
self.mass_extinction=mass_extinction
self.epoch_thresh=epoch_thresh
self.selector=selector
self.mutator = mutator
self.crossover = crossover
#Factory
self.factory=ClusterFactory(natoms,minimiser,composition,labels)
#PopulationList
self.population = PopulationList(natoms,self.factory,pop_size)
if restart is False:
while len(self.population) < self.population.max_size:
self.population.append(self.factory.get_random_cluster())
self.population.sort_energy()
else:
with open("restart.xyz",'r') as xyz_file:
self.population.read_xyz(xyz_file)
#Evolutionary progress
self.mean_energy_series=[]
self.mean_energy_series.append(self.population.get_mean_energy())
self.min_energy_series=[]
self.min_energy_series.append(self.population.get_lowest_energy())
class BatchGeneticAlgorithm(object):
'''The Birmingham Cluster Genetic Algorithm.
A new parallel version of the BCGA. The population is stored in a pele database and can be accessed by several processes simultaneously.
Parameters:
natoms- Number of atoms in cluster
minimiser- See bcga.gpaw_interface
Optional parameters:
composition- A list containing the number of atoms of each type
labels- A tuple orblist containing the names of each atom type (e.g. ["Au","Ag"]
pop_size- Number of clusters in population
max_generation- Number of generations to run GA
selector- Selection method for choosing parents (see bcga.selector)
offspring- Number of crossover operations in each generation
mutant_rate- Probability of any cluster producing a mutant
remove_duplicates- Remove identical clusters from population to prevent stagnation
restart- Read population from restart.xyz and continue a search
'''
def __init__(self,natoms,minimiser,
composition="default",labels=("X",),
pop_size=10,max_generation=10,
selector=TournamentSelector(3),
offspring=8,mutant_rate=0.1,remove_duplicates=False,
mutator=MutateReplace(),
crossover=DeavenHo()):
#Parameters
self.max_generation = max_generation
self.mutant_rate = mutant_rate
self.offspring=offspring
self.pop_size=pop_size
self.remove_duplicates=remove_duplicates
self.selector=selector
self.mutator = mutator
self.crossover = crossover
#Factory
self.factory=ClusterFactory(natoms,minimiser,composition,labels)
#PopulationList
self.population = PopulationList(natoms,self.factory,pop_size)
#Evolutionary progress
self.mean_energy_series=[]
self.min_energy_series=[]
self.db = Database(db="mydatabase.sqlite")
self.storage = self.db.minimum_adder()
def write_xyz(self,file_name="cluster.xyz"):
'''Open an xyz file and write the current population to it (non-blocking).'''
try:
with open(file_name,'w') as xyz_file:
self.population.write_xyz(xyz_file)
except IOError as err:
print("File error: "+str(err))
def read_xyz(self,file_name="restart.xyz"):
'''Read population from an xyz file (non-blocking for now).'''
self.population.mass_extinction(0)
try:
with open(file_name) as xyz_file:
self.population.read_xyz(xyz_file)
except:
print("No restart file available.")
def run(self):
'''Run the GA.'''
for generation in range(1,self.max_generation+1):
print ("Generation "+str(generation))
if self.db.number_of_minima() < self.population.max_size:
cluster=self.factory.get_random_cluster()
print("Filling population with random structure.")
else:
self.population.read_db(self.db)
if np.random < self.mutant_rate:
index=np.random.randint(0,len(self.population))
cluster=self.mutator.get_mutant(self.population[index])
print("Generating mutant of cluster "+str(index))
else:
indices = self.selector.select(self.population)
cluster=self.crossover.get_offspring(self.population[indices[0]],
self.population[indices[1]])
print("Generating offpsring of clusters "+str(indices[0])+" and "+str(indices[1]))
cluster.minimise()
#self.read_xyz("restart.xyz")
#self.population.append(cluster)
self.storage(cluster.energy,cluster._coords.flatten())
class GeneticAlgorithm(object):
'''The Birmingham Cluster Genetic Algorithm.
This is based on the original serial version of the BCGA.
Parameters:
natoms- Number of atoms in cluster
minimiser- See bcga.gpaw_interface
Optional parameters:
composition- A tuple or list containing the number of atoms of each type (e.g. ["Au","Ag"])
labels- A list containing the names of each atom type
pop_size- Number of clusters in population
max_generation- Number of generations to run GA
selector- Selection method for choosing parents (see bcga.selector)
offspring- Number of crossover operations in each generation
mutant_rate- Probability of any cluster producing a mutant
remove_duplicates- Remove identical clusters from population to prevent stagnation
mass_extinction- Re-set population if population stagnates
epoch_threshold- Mean population energy change that initiates mass extinction
restart- Read population from restart.xyz and continue a search
'''
def __init__(self,natoms,minimiser,
composition="default",labels=("X",),
pop_size=10,max_generation=10,
selector=TournamentSelector(3),
offspring=8,mutant_rate=0.1,remove_duplicates=False,
mass_extinction=False,epoch_thresh=1.e-6,
restart=False,
mutator=MutateReplace(),
crossover=DeavenHo()):
#Parameters
self.max_generation = max_generation
self.mutant_rate = mutant_rate
self.offspring=offspring
self.pop_size=pop_size
self.remove_duplicates=remove_duplicates
self.mass_extinction=mass_extinction
self.epoch_thresh=epoch_thresh
self.selector=selector
self.mutator = mutator
self.crossover = crossover
#Factory
self.factory=ClusterFactory(natoms,minimiser,composition,labels)
#PopulationList
self.population = PopulationList(natoms,self.factory,pop_size)
if restart is False:
while len(self.population) < self.population.max_size:
self.population.append(self.factory.get_random_cluster())
self.population.sort_energy()
else:
with open("restart.xyz",'r') as xyz_file:
self.population.read_xyz(xyz_file)
#Evolutionary progress
self.mean_energy_series=[]
self.mean_energy_series.append(self.population.get_mean_energy())
self.min_energy_series=[]
self.min_energy_series.append(self.population.get_lowest_energy())
def make_offspring(self):
'''Add offspring clusters to population'''
for i in range(0, self.offspring):
indices = self.selector.select(self.population)
mycluster=self.crossover.get_offspring(self.population[indices[0]],
self.population[indices[1]])
self.population.append(mycluster)
def make_mutants(self):
'''Add mutant clusters to population'''
for mycluster in self.population:
if np.random.uniform(0, 1) < self.mutant_rate:
self.population.append(self.mutator.get_mutant(mycluster))
def write_xyz(self,filename="cluster.xyz"):
'''Open an xyz file and write the current population to it'''
try:
with open(filename,'w') as xyz_file:
self.population.write_xyz(xyz_file)
except IOError as err:
print("File error: "+str(err))
def run(self):
'''Run the GA.'''
for generation in range(1,self.max_generation+1):
print ("Generation "+str(generation))
self.make_offspring()
self.make_mutants()
if self.remove_duplicates:
self.population.remove_duplicates()
self.population.truncate()
#Update time series
self.mean_energy_series.append(self.population.get_mean_energy())
self.min_energy_series.append(self.population.get_lowest_energy())
print("Lowest energy: "+str(self.population.get_lowest_energy())+" Mean energy: "+str(self.population.get_mean_energy()))
if self.mass_extinction:
diff = self.mean_energy_series[-2]-self.mean_energy_series[-1]
if 0 < diff < self.epoch_thresh:
print("New epoch. Energy change = "+str(diff))
self.population.mass_extinction()
while len(self.population) < self.population.max_size:
self.population.append(self.factory.get_random_cluster())
self.population.sort_energy()
self.write_xyz("restart.xyz")
class BatchGeneticAlgorithm(object):
'''The Birmingham Cluster Genetic Algorithm.
A new parallel version of the BCGA. The population is stored in a pele database and can be accessed by several processes simultaneously.
Parameters:
natoms- Number of atoms in cluster
minimiser- See bcga.gpaw_interface
Optional parameters:
composition- A list containing the number of atoms of each type
labels- A tuple orblist containing the names of each atom type (e.g. ["Au","Ag"]
pop_size- Number of clusters in population
max_generation- Number of generations to run GA
selector- Selection method for choosing parents (see bcga.selector)
offspring- Number of crossover operations in each generation
mutant_rate- Probability of any cluster producing a mutant
remove_duplicates- Remove identical clusters from population to prevent stagnation
restart- Read population from restart.xyz and continue a search
'''
def __init__(self,
natoms,
minimiser,
composition="default",
labels=("X", ),
pop_size=10,
max_generation=10,
selector=TournamentSelector(3),
offspring=8,
mutant_rate=0.1,
remove_duplicates=False,
mutator=MutateReplace(),
crossover=DeavenHo()):
#Parameters
self.max_generation = max_generation
self.mutant_rate = mutant_rate
self.offspring = offspring
self.pop_size = pop_size
self.remove_duplicates = remove_duplicates
self.selector = selector
self.mutator = mutator
self.crossover = crossover
#Factory
self.factory = ClusterFactory(natoms, minimiser, composition, labels)
#PopulationList
self.population = PopulationList(natoms, self.factory, pop_size)
#Evolutionary progress
self.mean_energy_series = []
self.min_energy_series = []
self.db = Database(db="mydatabase.sqlite")
self.storage = self.db.minimum_adder()
def write_xyz(self, file_name="cluster.xyz"):
'''Open an xyz file and write the current population to it (non-blocking).'''
try:
with open(file_name, 'w') as xyz_file:
self.population.write_xyz(xyz_file)
except IOError as err:
print("File error: " + str(err))
def read_xyz(self, file_name="restart.xyz"):
'''Read population from an xyz file (non-blocking for now).'''
self.population.mass_extinction(0)
try:
with open(file_name) as xyz_file:
self.population.read_xyz(xyz_file)
except:
print("No restart file available.")
def run(self):
'''Run the GA.'''
for generation in range(1, self.max_generation + 1):
print("Generation " + str(generation))
if self.db.number_of_minima() < self.population.max_size:
cluster = self.factory.get_random_cluster()
print("Filling population with random structure.")
else:
self.population.read_db(self.db)
if np.random < self.mutant_rate:
index = np.random.randint(0, len(self.population))
cluster = self.mutator.get_mutant(self.population[index])
print("Generating mutant of cluster " + str(index))
else:
indices = self.selector.select(self.population)
cluster = self.crossover.get_offspring(
self.population[indices[0]],
self.population[indices[1]])
print("Generating offpsring of clusters " +
str(indices[0]) + " and " + str(indices[1]))
cluster.minimise()
#self.read_xyz("restart.xyz")
#self.population.append(cluster)
self.storage(cluster.energy, cluster._coords.flatten())
class GeneticAlgorithm(object):
'''The Birmingham Cluster Genetic Algorithm.
This is based on the original serial version of the BCGA.
Parameters:
natoms- Number of atoms in cluster
minimiser- See bcga.gpaw_interface
Optional parameters:
composition- A tuple or list containing the number of atoms of each type (e.g. ["Au","Ag"])
labels- A list containing the names of each atom type
pop_size- Number of clusters in population
max_generation- Number of generations to run GA
selector- Selection method for choosing parents (see bcga.selector)
offspring- Number of crossover operations in each generation
mutant_rate- Probability of any cluster producing a mutant
remove_duplicates- Remove identical clusters from population to prevent stagnation
mass_extinction- Re-set population if population stagnates
epoch_threshold- Mean population energy change that initiates mass extinction
restart- Read population from restart.xyz and continue a search
'''
def __init__(self,
natoms,
minimiser,
composition="default",
labels=("X", ),
pop_size=10,
max_generation=10,
selector=TournamentSelector(3),
offspring=8,
mutant_rate=0.1,
remove_duplicates=False,
mass_extinction=False,
epoch_thresh=1.e-6,
restart=False,
mutator=MutateReplace(),
crossover=DeavenHo()):
#Parameters
self.max_generation = max_generation
self.mutant_rate = mutant_rate
self.offspring = offspring
self.pop_size = pop_size
self.remove_duplicates = remove_duplicates
self.mass_extinction = mass_extinction
self.epoch_thresh = epoch_thresh
self.selector = selector
self.mutator = mutator
self.crossover = crossover
#Factory
self.factory = ClusterFactory(natoms, minimiser, composition, labels)
#PopulationList
self.population = PopulationList(natoms, self.factory, pop_size)
if restart is False:
while len(self.population) < self.population.max_size:
self.population.append(self.factory.get_random_cluster())
self.population.sort_energy()
else:
with open("restart.xyz", 'r') as xyz_file:
self.population.read_xyz(xyz_file)
#Evolutionary progress
self.mean_energy_series = []
self.mean_energy_series.append(self.population.get_mean_energy())
self.min_energy_series = []
self.min_energy_series.append(self.population.get_lowest_energy())
def make_offspring(self):
'''Add offspring clusters to population'''
for i in range(0, self.offspring):
indices = self.selector.select(self.population)
mycluster = self.crossover.get_offspring(
self.population[indices[0]], self.population[indices[1]])
self.population.append(mycluster)
def make_mutants(self):
'''Add mutant clusters to population'''
for mycluster in self.population:
if np.random.uniform(0, 1) < self.mutant_rate:
self.population.append(self.mutator.get_mutant(mycluster))
def write_xyz(self, filename="cluster.xyz"):
'''Open an xyz file and write the current population to it'''
try:
with open(filename, 'w') as xyz_file:
self.population.write_xyz(xyz_file)
except IOError as err:
print("File error: " + str(err))
def run(self):
'''Run the GA.'''
for generation in range(1, self.max_generation + 1):
print("Generation " + str(generation))
self.make_offspring()
self.make_mutants()
if self.remove_duplicates:
self.population.remove_duplicates()
self.population.truncate()
#Update time series
self.mean_energy_series.append(self.population.get_mean_energy())
self.min_energy_series.append(self.population.get_lowest_energy())
print("Lowest energy: " +
str(self.population.get_lowest_energy()) + " Mean energy: " +
str(self.population.get_mean_energy()))
if self.mass_extinction:
diff = self.mean_energy_series[-2] - self.mean_energy_series[-1]
if 0 < diff < self.epoch_thresh:
print("New epoch. Energy change = " + str(diff))
self.population.mass_extinction()
while len(self.population) < self.population.max_size:
self.population.append(
self.factory.get_random_cluster())
self.population.sort_energy()
self.write_xyz("restart.xyz")
