Source code for ax.utils.testing.metrics.branin_backend_map

#!/usr/bin/env python3
# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.

from typing import Iterable, List, Optional

import numpy as np
from ax.core.map_data import MapKeyInfo
from ax.metrics.branin_map import BraninTimestampMapMetric
from ax.utils.testing.metrics.backend_simulator_map import (
    BackendSimulatorTimestampMapMetric,
)


[docs]class BraninBackendMapMetric( BackendSimulatorTimestampMapMetric, BraninTimestampMapMetric ): """A Branin ``BackendSimulatorTimestampMapMetric`` with a multiplicative factor of ``1 - exp(-rate * t)`` where ``t`` is the runtime of the trial.""" def __init__( self, name: str, param_names: List[str], map_key_infos: Optional[Iterable[MapKeyInfo]] = None, noise_sd: float = 0.0, lower_is_better: Optional[bool] = True, cache_evaluations: bool = True, rate: float = 0.5, delta_t: float = 1.0, ) -> None: """The ``BraninTimestampMapMetric`` integrated with the backend simulator. Args: name: Name of the metric. param_names: An ordered list of names of parameters to be passed to the deterministic function. noise_sd: Scale of normal noise added to the function result. lower_is_better: Flag for metrics which should be minimized. rate: Parameter of the multiplicative factor. delta_t: The time delta between intermediate results, used in ``convert_to_timestamps``. """ BackendSimulatorTimestampMapMetric.__init__( self, name=name, param_names=param_names, map_key_infos=map_key_infos if map_key_infos is not None else [MapKeyInfo(key="timestamp", default_value=0.0)], noise_sd=noise_sd, lower_is_better=lower_is_better, cache_evaluations=cache_evaluations, ) self.rate = rate self.delta_t = delta_t self._timestamp = -1
[docs] def convert_to_timestamps( self, start_time: Optional[float], end_time: float ) -> List[float]: """Given a starting and current time, get the list of intermediate timestamps at which we have observations.""" if start_time is None: # NOTE: This can be the case for trials on backend simulator # that are queued. return [] num_periods_running = (end_time - start_time) // self.delta_t return list(np.arange(num_periods_running) * self.delta_t)