Files
ray/python/ray/tune/suggest/hyperopt.py
T
SvenandEric Liang 60d4d5e1aa Remove future imports (#6724)
* Remove all __future__ imports from RLlib.

* Remove (object) again from tf_run_builder.py::TFRunBuilder.

* Fix 2xLINT warnings.

* Fix broken appo_policy import (must be appo_tf_policy)

* Remove future imports from all other ray files (not just RLlib).

* Remove future imports from all other ray files (not just RLlib).

* Remove future import blocks that contain `unicode_literals` as well.
Revert appo_tf_policy.py to appo_policy.py (belongs to another PR).

* Add two empty lines before Schedule class.

* Put back __future__ imports into determine_tests_to_run.py. Fails otherwise on a py2/print related error.
2020-01-09 00:15:48 -08:00

227 lines
9.1 KiB
Python

import numpy as np
import copy
import logging
from functools import partial
import pickle
try:
hyperopt_logger = logging.getLogger("hyperopt")
hyperopt_logger.setLevel(logging.WARNING)
import hyperopt as hpo
except ImportError:
hpo = None
from ray.tune.error import TuneError
from ray.tune.suggest.suggestion import SuggestionAlgorithm
logger = logging.getLogger(__name__)
class HyperOptSearch(SuggestionAlgorithm):
"""A wrapper around HyperOpt to provide trial suggestions.
Requires HyperOpt to be installed from source.
Uses the Tree-structured Parzen Estimators algorithm, although can be
trivially extended to support any algorithm HyperOpt uses. Externally
added trials will not be tracked by HyperOpt. Trials of the current run
can be saved using save method, trials of a previous run can be loaded
using restore method, thus enabling a warm start feature.
Parameters:
space (dict): HyperOpt configuration. Parameters will be sampled
from this configuration and will be used to override
parameters generated in the variant generation process.
max_concurrent (int): Number of maximum concurrent trials. Defaults
to 10.
metric (str): The training result objective value attribute.
mode (str): One of {min, max}. Determines whether objective is
minimizing or maximizing the metric attribute.
points_to_evaluate (list): Initial parameter suggestions to be run
first. This is for when you already have some good parameters
you want hyperopt to run first to help the TPE algorithm
make better suggestions for future parameters. Needs to be
a list of dict of hyperopt-named variables.
Choice variables should be indicated by their index in the
list (see example)
n_initial_points (int): number of random evaluations of the
objective function before starting to aproximate it with
tree parzen estimators. Defaults to 20.
random_state_seed (int, array_like, None): seed for reproducible
results. Defaults to None.
gamma (float in range (0,1)): parameter governing the tree parzen
estimators suggestion algorithm. Defaults to 0.25.
use_early_stopped_trials (bool): Whether to use early terminated
trial results in the optimization process.
Example:
>>> space = {
>>> 'width': hp.uniform('width', 0, 20),
>>> 'height': hp.uniform('height', -100, 100),
>>> 'activation': hp.choice("activation", ["relu", "tanh"])
>>> }
>>> current_best_params = [{
>>> 'width': 10,
>>> 'height': 0,
>>> 'activation': 0, # The index of "relu"
>>> }]
>>> algo = HyperOptSearch(
>>> space, max_concurrent=4, metric="mean_loss", mode="min",
>>> points_to_evaluate=current_best_params)
"""
def __init__(self,
space,
max_concurrent=10,
reward_attr=None,
metric="episode_reward_mean",
mode="max",
points_to_evaluate=None,
n_initial_points=20,
random_state_seed=None,
gamma=0.25,
**kwargs):
assert hpo is not None, "HyperOpt must be installed!"
from hyperopt.fmin import generate_trials_to_calculate
assert type(max_concurrent) is int and max_concurrent > 0
assert mode in ["min", "max"], "`mode` must be 'min' or 'max'!"
if reward_attr is not None:
mode = "max"
metric = reward_attr
logger.warning(
"`reward_attr` is deprecated and will be removed in a future "
"version of Tune. "
"Setting `metric={}` and `mode=max`.".format(reward_attr))
self._max_concurrent = max_concurrent
self._metric = metric
# hyperopt internally minimizes, so "max" => -1
if mode == "max":
self._metric_op = -1.
elif mode == "min":
self._metric_op = 1.
if n_initial_points is None:
self.algo = hpo.tpe.suggest
else:
self.algo = partial(
hpo.tpe.suggest, n_startup_jobs=n_initial_points)
if gamma is not None:
self.algo = partial(self.algo, gamma=gamma)
self.domain = hpo.Domain(lambda spc: spc, space)
if points_to_evaluate is None:
self._hpopt_trials = hpo.Trials()
self._points_to_evaluate = 0
else:
assert type(points_to_evaluate) == list
self._hpopt_trials = generate_trials_to_calculate(
points_to_evaluate)
self._hpopt_trials.refresh()
self._points_to_evaluate = len(points_to_evaluate)
self._live_trial_mapping = {}
if random_state_seed is None:
self.rstate = np.random.RandomState()
else:
self.rstate = np.random.RandomState(random_state_seed)
super(HyperOptSearch, self).__init__(**kwargs)
def _suggest(self, trial_id):
if self._num_live_trials() >= self._max_concurrent:
return None
if self._points_to_evaluate > 0:
new_trial = self._hpopt_trials.trials[self._points_to_evaluate - 1]
self._points_to_evaluate -= 1
else:
new_ids = self._hpopt_trials.new_trial_ids(1)
self._hpopt_trials.refresh()
# Get new suggestion from Hyperopt
new_trials = self.algo(new_ids, self.domain, self._hpopt_trials,
self.rstate.randint(2**31 - 1))
self._hpopt_trials.insert_trial_docs(new_trials)
self._hpopt_trials.refresh()
new_trial = new_trials[0]
self._live_trial_mapping[trial_id] = (new_trial["tid"], new_trial)
# Taken from HyperOpt.base.evaluate
config = hpo.base.spec_from_misc(new_trial["misc"])
ctrl = hpo.base.Ctrl(self._hpopt_trials, current_trial=new_trial)
memo = self.domain.memo_from_config(config)
hpo.utils.use_obj_for_literal_in_memo(self.domain.expr, ctrl,
hpo.base.Ctrl, memo)
suggested_config = hpo.pyll.rec_eval(
self.domain.expr,
memo=memo,
print_node_on_error=self.domain.rec_eval_print_node_on_error)
return copy.deepcopy(suggested_config)
def on_trial_result(self, trial_id, result):
ho_trial = self._get_hyperopt_trial(trial_id)
if ho_trial is None:
return
now = hpo.utils.coarse_utcnow()
ho_trial["book_time"] = now
ho_trial["refresh_time"] = now
def on_trial_complete(self,
trial_id,
result=None,
error=False,
early_terminated=False):
"""Notification for the completion of trial.
The result is internally negated when interacting with HyperOpt
so that HyperOpt can "maximize" this value, as it minimizes on default.
"""
ho_trial = self._get_hyperopt_trial(trial_id)
if ho_trial is None:
return
ho_trial["refresh_time"] = hpo.utils.coarse_utcnow()
if error:
ho_trial["state"] = hpo.base.JOB_STATE_ERROR
ho_trial["misc"]["error"] = (str(TuneError), "Tune Error")
self._hpopt_trials.refresh()
else:
self._process_result(trial_id, result, early_terminated)
del self._live_trial_mapping[trial_id]
def _process_result(self, trial_id, result, early_terminated=False):
ho_trial = self._get_hyperopt_trial(trial_id)
ho_trial["refresh_time"] = hpo.utils.coarse_utcnow()
if early_terminated and self._use_early_stopped is False:
ho_trial["state"] = hpo.base.JOB_STATE_ERROR
ho_trial["misc"]["error"] = (str(TuneError), "Tune Removed")
return
ho_trial["state"] = hpo.base.JOB_STATE_DONE
hp_result = self._to_hyperopt_result(result)
ho_trial["result"] = hp_result
self._hpopt_trials.refresh()
def _to_hyperopt_result(self, result):
return {"loss": self._metric_op * result[self._metric], "status": "ok"}
def _get_hyperopt_trial(self, trial_id):
if trial_id not in self._live_trial_mapping:
return
hyperopt_tid = self._live_trial_mapping[trial_id][0]
return [
t for t in self._hpopt_trials.trials if t["tid"] == hyperopt_tid
][0]
def _num_live_trials(self):
return len(self._live_trial_mapping)
def save(self, checkpoint_dir):
trials_object = (self._hpopt_trials, self.rstate.get_state())
with open(checkpoint_dir, "wb") as outputFile:
pickle.dump(trials_object, outputFile)
def restore(self, checkpoint_dir):
with open(checkpoint_dir, "rb") as inputFile:
trials_object = pickle.load(inputFile)
self._hpopt_trials = trials_object[0]
self.rstate.set_state(trials_object[1])