from __future__ import annotations
import itertools
import numpy as np
from ConfigSpace.configuration_space import Configuration
from ConfigSpace.hyperparameters import (
CategoricalHyperparameter,
Constant,
NumericalHyperparameter,
OrdinalHyperparameter,
)
from ConfigSpace.util import deactivate_inactive_hyperparameters
from smac.initial_design.abstract_initial_design import AbstractInitialDesign
__copyright__ = "Copyright 2022, automl.org"
__license__ = "3-clause BSD"
[docs]
class FactorialInitialDesign(AbstractInitialDesign):
"""Factorial initial design to select corner and middle configurations."""
def _select_configurations(self) -> list[Configuration]:
params = self._configspace.get_hyperparameters()
values = []
mid = []
for param in params:
if isinstance(param, Constant):
v = [param.value]
mid.append(param.value)
elif isinstance(param, NumericalHyperparameter):
v = [param.lower, param.upper]
mid.append(np.average([param.lower, param.upper]))
elif isinstance(param, CategoricalHyperparameter):
v = list(param.choices)
mid.append(param.choices[0])
elif isinstance(param, OrdinalHyperparameter):
v = [param.sequence[0], param.sequence[-1]]
length = len(param.sequence)
mid.append(param.sequence[int(length / 2)])
values.append(v)
factorial_design = itertools.product(*values)
configs = [self._configspace.get_default_configuration()]
# add middle point in space
conf_dict = dict([(p.name, v) for p, v in zip(params, mid)])
middle_conf = deactivate_inactive_hyperparameters(conf_dict, self._configspace)
configs.append(middle_conf)
# Add corner points
for design in factorial_design:
conf_dict = dict([(p.name, v) for p, v in zip(params, design)])
conf = deactivate_inactive_hyperparameters(conf_dict, self._configspace)
conf.origin = "Initial Design: Factorial"
configs.append(conf)
return configs