def default_termination(problem):
if problem.n_obj > 1:
termination = MultiObjectiveDefaultTermination()
else:
termination = SingleObjectiveDefaultTermination()
return termination
def create_optimization_run(
pop_size=pop_size_def,
n_offsprings=n_offsprings_def,
sampling=sampling_def,
crossover=crossover_def,
mutation=mutation_def,
eliminate_duplicates=True,
filename="foo",
# termination = get_termination("n_gen",50),
termination=MultiObjectiveDefaultTermination(
x_tol=x_tol_def,
cv_tol=cv_tol_def,
f_tol=f_tol_def,
nth_gen=nth_gen_def,
n_last=n_last_def,
n_max_gen=max_gen,
n_max_evals=n_max_evals_def,
),
lockdown_policy_control_days=lockdown_policy_control_days_def,
lockdown_policy_lower_limits=lockdown_policy_lower_limits_def, # can't use len(l_p_c_d) within function param def
lockdown_policy_upper_limits=lockdown_policy_upper_limits_def, # needs to be different from lower limit
testing_policy_control_days=testing_policy_control_days_def,
testing_policy_lower_limits=testing_policy_lower_limits_def,
testing_policy_upper_limits=testing_policy_upper_limits_def,
max_daily_tests=max_daily_tests_def,
p_ICU=p_ICU_def,
C_hos=C_hos_def,
T_rec=T_rec_def, # recovery time in years from end of experiment
**epidemic_model_params):
model, model_case = create_epidemic_model(**epidemic_model_params)
#print("DEBUG policy parameters:")
#print("ld days:", lockdown_policy_control_days)
#print("ld lolim: ", lockdown_policy_lower_limits)
#print("ld hilim:", lockdown_policy_upper_limits)
#print("t days:", testing_policy_control_days)
#print("t lolim: ", testing_policy_lower_limits)
#print("t hilim:", testing_policy_upper_limits)
problem = COVID_policy(
model, model_case, lockdown_policy_control_days,
lockdown_policy_lower_limits, lockdown_policy_upper_limits,
testing_policy_control_days, testing_policy_lower_limits,
testing_policy_upper_limits, max_daily_tests, p_ICU, C_hos, T_rec)
# create initial population here
initial_pop_x = get_sampling(
"real_random") # random sampling for first population
algorithm = NSGA2(pop_size=pop_size,
n_offsprings=n_offsprings,
sampling=initial_pop_x,
crossover=crossover,
mutation=mutation,
eliminate_duplicates=True)
return problem, algorithm, termination, model, model_case
def minimize(problem, algorithm, termination=None, **kwargs):
"""
Minimization of function of one or more variables, objectives and constraints.
This is used as a convenience function to execute several algorithms with default settings which turned
out to work for a test single. However, evolutionary computations utilizes the idea of customizing a
meta-algorithm. Customizing the algorithm using the object oriented interface is recommended to improve the
convergence.
Parameters
----------
problem : pymoo.problem
A problem object which is defined using pymoo.
algorithm : :class:`~pymoo.model.algorithm.Algorithm`
The algorithm object that should be used for the optimization.
termination : class or tuple
The termination criterion that is used to stop the algorithm.
Returns
-------
res : :class:`~pymoo.model.result.Result`
The optimization result represented as an object.
"""
# create a copy of the algorithm object to ensure no side-effects
algorithm = copy.deepcopy(algorithm)
# set the termination criterion and store it in the algorithm object
if termination is None:
termination = None
elif not isinstance(termination, Termination):
if isinstance(termination, str):
termination = get_termination(termination)
else:
termination = get_termination(*termination)
# initialize the method given a problem
algorithm.initialize(problem, termination=termination, **kwargs)
if algorithm.termination is None:
if problem.n_obj > 1:
algorithm.termination = MultiObjectiveDefaultTermination()
else:
algorithm.termination = SingleObjectiveDefaultTermination()
# actually execute the algorithm
res = algorithm.solve()
# store the copied algorithm in the result object
res.algorithm = algorithm
return res
def termination(self):
termination = MultiObjectiveDefaultTermination(
x_tol=self.x_tol,
cv_tol=self.cv_tol,
f_tol=self.f_tol,
nth_gen=self.nth_gen,
n_last=self.n_last,
n_max_gen=self.n_max_gen,
n_max_evals=self.n_max_evals)
return termination
def __init__(self,
CR=0.3,
F=None,
variant="DE/rand/1/bin",
mutation=PM(eta=15),
**kwargs):
super().__init__(CR=CR,
F=F,
variant=variant,
mutation=mutation,
display=MultiObjectiveDisplay(),
**kwargs)
self.default_termination = MultiObjectiveDefaultTermination()
def calculate_pareto_front(
state_space_equation,
tau,
y_measured,
x0,
xl: Union[np.ndarray, None],
xu: Union[np.ndarray, None],
n_var: int,
n_obj: int,
normalize_quaternions: bool,
n_constr=0,
pop_size=100,
n_max_gen=1000,
verbose=True,
display=MyDisplay(),
) -> Result:
# calculate pareto frontier
problem = UUVParameterProblem(
state_space_equation,
tau,
y_measured,
x0,
n_var=n_var,
n_obj=n_obj,
n_constr=n_constr,
xl=xl,
xu=xu,
normalize_quaternions=normalize_quaternions,
)
algorithm = NSGA2(
pop_size=pop_size,
# n_offsprings=int(pop_size / 2),
crossover=SimulatedBinaryCrossover(eta=15, prob=0.9),
mutation=PolynomialMutation(prob=None, eta=15),
)
termination_default = MultiObjectiveDefaultTermination(n_max_gen=n_max_gen)
termination_design_space = DesignSpaceToleranceTermination(n_max_gen=n_max_gen)
termination_generations = get_termination("n_gen", 100)
res = minimize(
problem,
algorithm,
termination_default,
verbose=verbose,
display=display,
)
return res
def __init__(self,
pop_size=100,
sampling=FloatRandomSampling(),
selection=TournamentSelection(func_comp=binary_tournament),
crossover=SBX(eta=15, prob=0.9),
mutation=PM(prob=None, eta=20),
eliminate_duplicates=True,
n_offsprings=None,
display=MultiObjectiveDisplay(),
**kwargs):
"""
Adapted from:
Panichella, A. (2019). An adaptive evolutionary algorithm based on non-euclidean geometry for many-objective
optimization. GECCO 2019 - Proceedings of the 2019 Genetic and Evolutionary Computation Conference, July, 595–603.
https://doi.org/10.1145/3321707.3321839
Parameters
----------
pop_size : {pop_size}
sampling : {sampling}
selection : {selection}
crossover : {crossover}
mutation : {mutation}
eliminate_duplicates : {eliminate_duplicates}
n_offsprings : {n_offsprings}
"""
super().__init__(pop_size=pop_size,
sampling=sampling,
selection=selection,
crossover=crossover,
mutation=mutation,
survival=AGEMOEASurvival(),
eliminate_duplicates=eliminate_duplicates,
n_offsprings=n_offsprings,
display=display,
advance_after_initial_infill=True,
**kwargs)
self.default_termination = MultiObjectiveDefaultTermination()
self.tournament_type = 'comp_by_rank_and_crowding'
def __init__(self,
pop_size=100,
sampling=FloatRandomSampling(),
selection=TournamentSelection(func_comp=binary_tournament),
crossover=SimulatedBinaryCrossover(eta=15, prob=0.9),
mutation=PolynomialMutation(prob=None, eta=20),
survival=RankAndCrowdingSurvival(),
eliminate_duplicates=True,
n_offsprings=None,
display=MultiObjectiveDisplay(),
**kwargs):
"""
Parameters
----------
pop_size : {pop_size}
sampling : {sampling}
selection : {selection}
crossover : {crossover}
mutation : {mutation}
eliminate_duplicates : {eliminate_duplicates}
n_offsprings : {n_offsprings}
"""
super().__init__(pop_size=pop_size,
sampling=sampling,
selection=selection,
crossover=crossover,
mutation=mutation,
survival=survival,
eliminate_duplicates=eliminate_duplicates,
n_offsprings=n_offsprings,
display=display,
advance_after_initial_infill=True,
**kwargs)
self.default_termination = MultiObjectiveDefaultTermination()
self.tournament_type = 'comp_by_dom_and_crowding'
tic = time.perf_counter()
problem = MyProblem()
#BRGKA algorithm parameters- can be altered
algorithm = BRKGA(n_elites=250,
n_offsprings=800,
n_mutants=100,
bias=0.3,
eliminate_duplicates=True)
#termination criteria- can be altered
termination = MultiObjectiveDefaultTermination(x_tol=1e-8,
cv_tol=1e-6,
f_tol=0.0025,
nth_gen=5,
n_last=300,
n_max_gen=300,
n_max_evals=40000)
#execute problem
res = minimize(problem,
algorithm,
termination,
seed=1,
pf=problem.pareto_front(use_cache=False),
save_history=True,
verbose=True)
# collect the population in each generation
pop_each_gen = [a.pop for a in res.history]
def main():
"""
Optimization module main driver
"""
# Define initialization objects
initializer_class = SmellInitialization if config.WARM_START else RandomInitialization
initializer_object = initializer_class(
udb_path=config.UDB_PATH,
population_size=config.POPULATION_SIZE,
lower_band=config.LOWER_BAND,
upper_band=config.UPPER_BAND
)
# -------------------------------------------
# Define optimization problems
problems = list() # 0: Genetic (Single), 1: NSGA-II (Multi), 2: NSGA-III (Many) objectives problems
problems.append(
ProblemSingleObjective(
n_objectives=config.NUMBER_OBJECTIVES,
n_refactorings_lowerbound=config.LOWER_BAND,
n_refactorings_upperbound=config.UPPER_BAND,
evaluate_in_parallel=False,
)
)
problems.append(
ProblemMultiObjective(
n_objectives=config.NUMBER_OBJECTIVES,
n_refactorings_lowerbound=config.LOWER_BAND,
n_refactorings_upperbound=config.UPPER_BAND,
evaluate_in_parallel=False,
)
)
problems.append(
ProblemManyObjective(
n_objectives=config.NUMBER_OBJECTIVES,
n_refactorings_lowerbound=config.LOWER_BAND,
n_refactorings_upperbound=config.UPPER_BAND,
evaluate_in_parallel=False,
verbose_design_metrics=True,
)
)
# Define search algorithms
algorithms = list()
# 1: GA
alg1 = GA(
pop_size=config.POPULATION_SIZE,
sampling=PopulationInitialization(initializer_object),
crossover=AdaptiveSinglePointCrossover(prob=config.CROSSOVER_PROBABILITY),
# crossover=get_crossover("real_k_point", n_points=2),
mutation=BitStringMutation(prob=config.MUTATION_PROBABILITY, initializer=initializer_object),
eliminate_duplicates=ElementwiseDuplicateElimination(cmp_func=is_equal_2_refactorings_list),
n_gen=config.NGEN,
)
algorithms.append(alg1)
# 2: NSGA-II
alg2 = NSGA2(
pop_size=config.POPULATION_SIZE,
sampling=PopulationInitialization(initializer_object),
crossover=AdaptiveSinglePointCrossover(prob=config.CROSSOVER_PROBABILITY),
# crossover=get_crossover("real_k_point", n_points=2),
mutation=BitStringMutation(prob=config.MUTATION_PROBABILITY, initializer=initializer_object),
eliminate_duplicates=ElementwiseDuplicateElimination(cmp_func=is_equal_2_refactorings_list),
n_gen=config.NGEN,
)
algorithms.append(alg2)
# 3: NSGA-III
# pop_size must be equal or larger than the number of reference directions
number_of_references_points = config.POPULATION_SIZE - int(config.POPULATION_SIZE * 0.20)
ref_dirs = get_reference_directions(
'energy', # algorithm
config.NUMBER_OBJECTIVES, # number of objectives
number_of_references_points, # number of reference directions
seed=1
)
alg3 = NSGA3(
ref_dirs=ref_dirs,
pop_size=config.POPULATION_SIZE, # 200
sampling=PopulationInitialization(initializer_object),
selection=TournamentSelection(func_comp=binary_tournament),
crossover=AdaptiveSinglePointCrossover(prob=config.CROSSOVER_PROBABILITY, ),
# crossover=get_crossover("real_k_point", n_points=2),
mutation=BitStringMutation(prob=config.MUTATION_PROBABILITY, initializer=initializer_object),
eliminate_duplicates=ElementwiseDuplicateElimination(cmp_func=is_equal_2_refactorings_list),
n_gen=config.NGEN,
)
algorithms.append(alg3)
# Termination of algorithms
my_termination = MultiObjectiveDefaultTermination(
x_tol=None,
cv_tol=None,
f_tol=0.0015,
nth_gen=5,
n_last=5,
n_max_gen=config.MAX_ITERATIONS, # about 1000 - 1400
n_max_evals=1e6
)
# Do optimization for various problems with various algorithms
res = minimize(
problem=problems[config.PROBLEM],
algorithm=algorithms[config.PROBLEM],
termination=my_termination,
seed=1,
verbose=False,
copy_algorithm=True,
copy_termination=True,
save_history=False,
callback=LogCallback(),
)
# np.save('checkpoint', res.algorithm)
# Log results
logger.info(f"***** Algorithm was finished in {res.algorithm.n_gen + config.NGEN} generations *****")
logger.info(" ")
logger.info("============ time information ============")
logger.info(f"Start time: {datetime.fromtimestamp(res.start_time).strftime('%Y-%m-%d %H:%M:%S')}")
logger.info(f"End time: {datetime.fromtimestamp(res.end_time).strftime('%Y-%m-%d %H:%M:%S')}")
logger.info(f"Execution time in seconds: {res.exec_time}")
logger.info(f"Execution time in minutes: {res.exec_time / 60}")
logger.info(f"Execution time in hours: {res.exec_time / (60 * 60)}")
# logger.info(f"Number of generations: {res.algorithm.n_gen}")
# logger.info(f"Number of generations", res.algorithm.termination)
# Log optimum solutions
logger.info("============ All opt solutions ============")
for i, ind in enumerate(res.opt):
logger.info(f'Opt refactoring sequence {i}:')
logger.info(ind.X)
logger.info(f'Opt refactoring sequence corresponding objectives vector {i}:')
logger.info(ind.F)
logger.info("-" * 75)
# Log best refactorings
logger.info("============ Best refactoring sequences (a set of non-dominated solutions) ============")
for i, ind in enumerate(res.X):
logger.info(f'Best refactoring sequence {i}:')
logger.info(ind)
logger.info("-" * 75)
logger.info("============ Best objective values (a set of non-dominated solutions) ============")
for i, ind_objective in enumerate(res.F):
logger.info(f'Best refactoring sequence corresponding objectives vector {i}:')
logger.info(ind_objective)
logger.info("-" * 75)
# Save best refactorings
population_trimmed = []
objective_values_content = ''
for chromosome in res.X:
chromosome_new = []
if config.PROBLEM == 0: # i.e., single objective problem
for gene_ in chromosome:
chromosome_new.append((gene_.name, gene_.params))
else:
for gene_ in chromosome[0]:
chromosome_new.append((gene_.name, gene_.params))
population_trimmed.append(chromosome_new)
for objective_vector in res.F:
objective_values_content += f'{res.algorithm.n_gen + config.NGEN},'
if config.PROBLEM == 0:
objective_values_content += f'{objective_vector},'
else:
for objective_ in objective_vector:
objective_values_content += f'{objective_},'
objective_values_content += '\n'
best_refactoring_sequences_path = os.path.join(
config.PROJECT_LOG_DIR,
f'best_refactoring_sequences_after_{res.algorithm.n_gen + config.NGEN}gens.json'
)
with open(best_refactoring_sequences_path, mode='w', encoding='utf-8') as fp:
json.dump(population_trimmed, fp, indent=4)
best_refactoring_sequences_objectives_path = os.path.join(
config.PROJECT_LOG_DIR,
f'best_refactoring_sequences_objectives_after_{res.algorithm.n_gen + config.NGEN}gens.csv'
)
with open(best_refactoring_sequences_objectives_path, mode='w', encoding='utf-8') as fp:
fp.write(objective_values_content)
try:
pf = res.F
# dm = HighTradeoffPoints()
dm = get_decision_making("high-tradeoff")
I = dm.do(pf)
logger.info("============ High-tradeoff points refactoring sequences ============")
for i, ind in enumerate(res.X[I]):
logger.info(f'High tradeoff points refactoring sequence {i}:')
logger.info(ind)
logger.info("-" * 75)
logger.info("============ High-tradeoff points objective values ============")
for i, ind_objective in enumerate(pf[I]):
logger.info(f'High-tradeoff points refactoring sequence corresponding objectives vector {i}:')
logger.info(ind_objective)
logger.info("-" * 75)
logger.info("High-tradeoff points mean:")
logger.info(np.mean(pf[I], axis=0))
logger.info("High-tradeoff points median:")
logger.info(np.median(pf[I], axis=0))
# Save high-tradeoff refactorings
population_trimmed = []
objective_values_content = ''
for chromosome in res.X[I]:
chromosome_new = []
if config.PROBLEM == 0: # i.e., single objective problem
for gene_ in chromosome:
chromosome_new.append((gene_.name, gene_.params))
else:
for gene_ in chromosome[0]:
chromosome_new.append((gene_.name, gene_.params))
population_trimmed.append(chromosome_new)
for objective_vector in pf[I]:
objective_values_content += f'{res.algorithm.n_gen + config.NGEN},'
if config.PROBLEM == 0:
objective_values_content += f'{objective_vector},'
else:
for objective_ in objective_vector:
objective_values_content += f'{objective_},'
objective_values_content += '\n'
high_tradeoff_path = os.path.join(
config.PROJECT_LOG_DIR,
f'high_tradeoff_points_refactoring_after_{res.algorithm.n_gen + config.NGEN}gens.json'
)
with open(high_tradeoff_path, mode='w', encoding='utf-8') as fp:
json.dump(population_trimmed, fp, indent=4)
high_tradeoff_path_objectives_path = os.path.join(
config.PROJECT_LOG_DIR,
f'high_tradeoff_points_after_{res.algorithm.n_gen + config.NGEN}gens.csv'
)
with open(high_tradeoff_path_objectives_path, mode='w', encoding='utf-8') as fp:
fp.write(objective_values_content)
except:
logger.error("No multi-optimal solutions (error in computing high tradeoff points)!")
algorithm = NSGA2(
pop_size=200, #100,#40, # initial population size
n_offsprings=100, #50,#10, # new individuals per generation
sampling=get_sampling("real_random"),
crossover=get_crossover("real_sbx", prob=0.9, eta=15),
mutation=get_mutation("real_pm", eta=20),
eliminate_duplicates=True)
# =============================================================================
# #Define termination criteria
# =============================================================================
#https://pymoo.org/interface/termination.html
termination = MultiObjectiveDefaultTermination(
x_tol=1e-8,
cv_tol=1e-6,
f_tol=0.0025,
nth_gen=5,
n_last=30,
n_max_gen=30, # maximal number of generations
n_max_evals=100000)
# =============================================================================
# #Solve the problem (Optimization)
# =============================================================================
#https://pymoo.org/interface/result.html
res = minimize(
problem,
algorithm,
termination,
seed=1,
#pf=problem.pareto_front(use_cache=False),
save_history=True,
def main():
# Define search algorithms
algorithms = list()
# 1: GA
algorithm = GA(
pop_size=config.POPULATION_SIZE,
sampling=PureRandomInitialization(),
crossover=AdaptiveSinglePointCrossover(prob=0.9),
# crossover=get_crossover("real_k_point", n_points=2),
mutation=BitStringMutation(prob=0.1),
eliminate_duplicates=ElementwiseDuplicateElimination(
cmp_func=is_equal_2_refactorings_list))
algorithms.append(algorithm)
# 2: NSGA II
algorithm = NSGA2(
pop_size=config.POPULATION_SIZE,
sampling=PureRandomInitialization(),
crossover=AdaptiveSinglePointCrossover(prob=0.9),
# crossover=get_crossover("real_k_point", n_points=2),
mutation=BitStringMutation(prob=0.1),
eliminate_duplicates=ElementwiseDuplicateElimination(
cmp_func=is_equal_2_refactorings_list))
algorithms.append(algorithm)
# 3: NSGA III
# pop_size must be equal or larger than the number of reference directions
number_of_references_points = config.POPULATION_SIZE - int(
config.POPULATION_SIZE * 0.20)
ref_dirs = get_reference_directions(
'energy', # algorithm
8, # number of objectives
number_of_references_points, # number of reference directions
seed=1)
algorithm = NSGA3(
ref_dirs=ref_dirs,
pop_size=config.POPULATION_SIZE, # 200
sampling=PureRandomInitialization(),
selection=TournamentSelection(func_comp=binary_tournament),
crossover=AdaptiveSinglePointCrossover(prob=0.8),
# crossover=get_crossover("real_k_point", n_points=2),
mutation=BitStringMutation(prob=0.1),
eliminate_duplicates=ElementwiseDuplicateElimination(
cmp_func=is_equal_2_refactorings_list))
algorithms.append(algorithm)
# -------------------------------------------
# Define problems
problems = list()
problems.append(
ProblemSingleObjective(n_refactorings_lowerbound=config.LOWER_BAND,
n_refactorings_upperbound=config.UPPER_BAND))
problems.append(
ProblemMultiObjective(n_refactorings_lowerbound=config.LOWER_BAND,
n_refactorings_upperbound=config.UPPER_BAND))
problems.append(
ProblemManyObjective(n_refactorings_lowerbound=config.LOWER_BAND,
n_refactorings_upperbound=config.UPPER_BAND,
evaluate_in_parallel=True))
# Termination of algorithms
my_termination = MultiObjectiveDefaultTermination(
x_tol=None,
cv_tol=None,
f_tol=0.0015,
nth_gen=10,
n_last=20,
n_max_gen=config.MAX_ITERATIONS, # about 1000 - 1400
n_max_evals=1e6)
# Do optimization for various problems with various algorithms
res = minimize(
problem=problems[2],
algorithm=algorithms[2],
termination=my_termination,
seed=1,
verbose=False,
copy_algorithm=True,
copy_termination=True,
save_history=False,
)
# np.save('checkpoint', res.algorithm)
# Log results
logger.info("\n** FINISHED **\n")
logger.info(
"Best refactoring sequences (a set of non-dominated solutions):")
logger.info(res.X)
logger.info("Best objective values (a set of non-dominated solutions):")
logger.info(res.F)
logger.info("=" * 75)
logger.info("Other solutions:")
for ind in res.opt:
logger.info(ind.X)
logger.info(ind.F)
logger.info("-" * 50)
logger.info("=" * 75)
logger.info(f"Start time: {res.start_time}")
logger.info(f"End time: {res.end_time}")
logger.info(f"Execution time in seconds: {res.exec_time}")
logger.info(f"Execution time in minutes: {res.exec_time / 60}")
logger.info(f"Execution time in hours: {res.exec_time / (60 * 60)}")
logger.info(f"Number of generations: {res.algorithm.n_gen}")
# logger.info(f"Number of generations", res.algorithm.termination)
pf = res.F
# dm = HighTradeoffPoints()
dm = get_decision_making("high-tradeoff")
try:
I = dm.do(pf)
logger.info(f"High tradeoff points: {pf[I][0]}")
logger.info(
f"High tradeoff points corresponding refactorings: {res.X[I]}")
logger.info(
f"The mean improvement of quality attributes: {np.mean(pf[I][0], axis=0)}"
)
logger.info(
f"The median improvement of quality attributes: {np.median(pf[I][0], axis=0)}"
)
except:
logger.info(
"No multi optimal solutions (error in computing high tradeoff points)!"
)
job = "constraint_analysis"
T = np.pi / (2 * 0.125)
#inv_G_ls = np.linspace(0.5,5,10) * T
inv_G_ls = [0.001 * T] #np.logspace(-2, 0, 10)[:5] * T
for num, inv_G in enumerate(inv_G_ls):
dim = (3, 2) # dimension of the problem
s, d = dim
N = (s - 2) * d
repeat = 1
r_min = 0.1
# -----------------------------------------------------------------------------
# Optimization parameters:
termination = MultiObjectiveDefaultTermination(x_tol=1e-8,
f_tol=10 - 8,
n_max_gen=10) # max=300
objs = [
lambda site_w_gt: OpenQT(s,
d,
np.array(site_w_gt[:(s - 2) * d]),
np.array(site_w_gt[(s - 2) * d:-1]),
Gamma=1 / inv_G,
n_p=3,
g_t=site_w_gt[-1]).T_r(epabs=0.01, limit=100)[
0]
]
constr_ieq = constr(s, d, r_min, bc=True)
def minimize(problem, algorithm, termination=None, **kwargs):
"""
Minimization of function of one or more variables, objectives and constraints.
This is used as a convenience function to execute several algorithms with default settings which turned
out to work for a test single. However, evolutionary computations utilizes the idea of customizing a
meta-algorithm. Customizing the algorithm using the object oriented interface is recommended to improve the
convergence.
Parameters
----------
problem : :class:`~pymoo.model.problem.Problem`
A problem object which is defined using pymoo.
algorithm : :class:`~pymoo.model.algorithm.Algorithm`
The algorithm object that should be used for the optimization.
termination : :class:`~pymoo.model.termination.Termination` or tuple
The termination criterion that is used to stop the algorithm.
seed : integer
The random seed to be used.
verbose : bool
Whether output should be printed or not.
display : :class:`~pymoo.util.display.Display`
Each algorithm has a default display object for printouts. However, it can be overwritten if desired.
callback : :class:`~pymoo.model.callback.Callback`
A callback object which is called each iteration of the algorithm.
save_history : bool
Whether the history should be stored or not.
Returns
-------
res : :class:`~pymoo.model.result.Result`
The optimization result represented as an object.
"""
# create a copy of the algorithm object to ensure no side-effects
algorithm = copy.deepcopy(algorithm)
# get the termination if provided as a tuple - create an object
if termination is not None and not isinstance(termination, Termination):
if isinstance(termination, str):
termination = get_termination(termination)
else:
termination = get_termination(*termination)
# initialize the algorithm object given a problem
algorithm.initialize(problem, termination=termination, **kwargs)
# if no termination could be found add the default termination either for single or multi objective
if algorithm.termination is None:
if problem.n_obj > 1:
algorithm.termination = MultiObjectiveDefaultTermination()
else:
algorithm.termination = SingleObjectiveDefaultTermination()
# actually execute the algorithm
res = algorithm.solve()
# store the deep copied algorithm in the result object
res.algorithm = algorithm
return res
