1
|
|
|
# Author: Simon Blanke |
2
|
|
|
# Email: [email protected] |
3
|
|
|
# License: MIT License |
4
|
|
|
|
5
|
|
|
import time |
6
|
|
|
import random |
7
|
|
|
|
8
|
|
|
import numpy as np |
9
|
|
|
import pandas as pd |
10
|
|
|
|
11
|
|
|
from multiprocessing.managers import DictProxy |
12
|
|
|
|
13
|
|
|
from .progress_bar import ProgressBarLVL0, ProgressBarLVL1 |
14
|
|
|
from .times_tracker import TimesTracker |
15
|
|
|
from .memory import Memory |
16
|
|
|
from .print_info import print_info |
17
|
|
|
from .init_positions import Initializer |
18
|
|
|
|
19
|
|
|
|
20
|
|
|
def time_exceeded(start_time, max_time): |
21
|
|
|
run_time = time.time() - start_time |
22
|
|
|
return max_time and run_time > max_time |
23
|
|
|
|
24
|
|
|
|
25
|
|
|
def score_exceeded(score_best, max_score): |
26
|
|
|
return max_score and score_best >= max_score |
27
|
|
|
|
28
|
|
|
|
29
|
|
|
def no_change(score_new_list, early_stopping): |
30
|
|
|
if "n_iter_no_change" not in early_stopping: |
31
|
|
|
print( |
32
|
|
|
"Warning n_iter_no_change-parameter must be set in order for early stopping to work" |
33
|
|
|
) |
34
|
|
|
return False |
35
|
|
|
|
36
|
|
|
n_iter_no_change = early_stopping["n_iter_no_change"] |
37
|
|
|
if len(score_new_list) <= n_iter_no_change: |
38
|
|
|
return False |
39
|
|
|
|
40
|
|
|
scores_np = np.array(score_new_list) |
41
|
|
|
|
42
|
|
|
max_score = max(score_new_list) |
43
|
|
|
max_index = np.argmax(scores_np) |
44
|
|
|
length_pos = len(score_new_list) |
45
|
|
|
|
46
|
|
|
diff = length_pos - max_index |
47
|
|
|
|
48
|
|
|
if diff > n_iter_no_change: |
49
|
|
|
return True |
50
|
|
|
|
51
|
|
|
first_n = length_pos - n_iter_no_change |
52
|
|
|
scores_first_n = score_new_list[:first_n] |
53
|
|
|
|
54
|
|
|
max_first_n = max(scores_first_n) |
55
|
|
|
|
56
|
|
|
if "tol_abs" in early_stopping and early_stopping["tol_abs"] is not None: |
57
|
|
|
tol_abs = early_stopping["tol_abs"] |
58
|
|
|
|
59
|
|
|
if abs(max_first_n - max_score) < tol_abs: |
60
|
|
|
return True |
61
|
|
|
|
62
|
|
|
if "tol_rel" in early_stopping and early_stopping["tol_rel"] is not None: |
63
|
|
|
tol_rel = early_stopping["tol_rel"] |
64
|
|
|
|
65
|
|
|
percent_imp = ((max_score - max_first_n) / abs(max_first_n)) * 100 |
66
|
|
|
if percent_imp < tol_rel: |
67
|
|
|
return True |
68
|
|
|
|
69
|
|
|
|
70
|
|
|
def set_random_seed(nth_process, random_state): |
71
|
|
|
""" |
72
|
|
|
Sets the random seed separately for each thread |
73
|
|
|
(to avoid getting the same results in each thread) |
74
|
|
|
""" |
75
|
|
|
if nth_process is None: |
76
|
|
|
nth_process = 0 |
77
|
|
|
|
78
|
|
|
if random_state is None: |
79
|
|
|
random_state = np.random.randint(0, high=2 ** 31 - 2, dtype=np.int64) |
80
|
|
|
|
81
|
|
|
random.seed(random_state + nth_process) |
82
|
|
|
np.random.seed(random_state + nth_process) |
83
|
|
|
|
84
|
|
|
|
85
|
|
|
class Search(TimesTracker): |
86
|
|
|
def __init__(self): |
87
|
|
|
super().__init__() |
88
|
|
|
|
89
|
|
|
self.optimizers = [] |
90
|
|
|
self.new_results_list = [] |
91
|
|
|
self.all_results_list = [] |
92
|
|
|
|
93
|
|
|
@TimesTracker.eval_time |
94
|
|
|
def _score(self, pos): |
95
|
|
|
return self.score(pos) |
96
|
|
|
|
97
|
|
|
@TimesTracker.iter_time |
98
|
|
|
def _initialization(self, init_pos, nth_iter): |
99
|
|
|
self.nth_iter = nth_iter |
100
|
|
|
self.best_score = self.p_bar.score_best |
101
|
|
|
|
102
|
|
|
self.init_pos(init_pos) |
103
|
|
|
|
104
|
|
|
score_new = self._score(init_pos) |
105
|
|
|
self.evaluate(score_new) |
106
|
|
|
|
107
|
|
|
self.p_bar.update(score_new, init_pos, nth_iter) |
108
|
|
|
|
109
|
|
|
@TimesTracker.iter_time |
110
|
|
|
def _iteration(self, nth_iter): |
111
|
|
|
self.nth_iter = nth_iter |
112
|
|
|
self.best_score = self.p_bar.score_best |
113
|
|
|
|
114
|
|
|
pos_new = self.iterate() |
115
|
|
|
|
116
|
|
|
score_new = self._score(pos_new) |
117
|
|
|
self.evaluate(score_new) |
118
|
|
|
|
119
|
|
|
self.p_bar.update(score_new, pos_new, nth_iter) |
120
|
|
|
|
121
|
|
|
def _init_search(self): |
122
|
|
|
self.stop = False |
123
|
|
|
|
124
|
|
|
if "progress_bar" in self.verbosity: |
125
|
|
|
self.p_bar = ProgressBarLVL1( |
126
|
|
|
self.nth_process, self.n_iter, self.objective_function |
127
|
|
|
) |
128
|
|
|
else: |
129
|
|
|
self.p_bar = ProgressBarLVL0( |
130
|
|
|
self.nth_process, self.n_iter, self.objective_function |
131
|
|
|
) |
132
|
|
|
|
133
|
|
|
set_random_seed(self.nth_process, self.random_state) |
134
|
|
|
|
135
|
|
|
def _early_stop(self): |
136
|
|
|
if self.stop: |
137
|
|
|
return |
138
|
|
|
|
139
|
|
|
if self.max_time and time_exceeded(self.start_time, self.max_time): |
140
|
|
|
self.stop = True |
141
|
|
|
elif self.max_score and score_exceeded(self.p_bar.score_best, self.max_score): |
142
|
|
|
self.stop = True |
143
|
|
|
elif self.early_stopping and no_change( |
144
|
|
|
self.score_new_list, self.early_stopping |
145
|
|
|
): |
146
|
|
|
self.stop = True |
147
|
|
|
|
148
|
|
|
def print_info(self, *args): |
149
|
|
|
print_info(*args) |
150
|
|
|
|
151
|
|
|
def search( |
152
|
|
|
self, |
153
|
|
|
objective_function, |
154
|
|
|
n_iter, |
155
|
|
|
max_time=None, |
156
|
|
|
max_score=None, |
157
|
|
|
early_stopping=None, |
158
|
|
|
memory=True, |
159
|
|
|
memory_warm_start=None, |
160
|
|
|
verbosity=["progress_bar", "print_results", "print_times"], |
161
|
|
|
random_state=None, |
162
|
|
|
nth_process=None, |
163
|
|
|
): |
164
|
|
|
self.start_time = time.time() |
165
|
|
|
|
166
|
|
|
if verbosity is False: |
167
|
|
|
verbosity = [] |
168
|
|
|
|
169
|
|
|
self.objective_function = objective_function |
170
|
|
|
self.n_iter = n_iter |
171
|
|
|
self.max_time = max_time |
172
|
|
|
self.max_score = max_score |
173
|
|
|
self.early_stopping = early_stopping |
174
|
|
|
self.memory = memory |
175
|
|
|
self.memory_warm_start = memory_warm_start |
176
|
|
|
self.verbosity = verbosity |
177
|
|
|
self.random_state = random_state |
178
|
|
|
self.nth_process = nth_process |
179
|
|
|
|
180
|
|
|
self._init_search() |
181
|
|
|
|
182
|
|
|
# get init positions |
183
|
|
|
init = Initializer(self.conv) |
184
|
|
|
self.init_positions = init.set_pos(self.initialize) |
185
|
|
|
|
186
|
|
|
if isinstance(memory, DictProxy): |
187
|
|
|
mem = Memory(memory_warm_start, self.conv, dict_proxy=memory) |
188
|
|
|
self.score = self.results_mang.score(mem.memory(objective_function)) |
189
|
|
|
elif memory is True: |
190
|
|
|
mem = Memory(memory_warm_start, self.conv) |
191
|
|
|
self.score = self.results_mang.score(mem.memory(objective_function)) |
192
|
|
|
else: |
193
|
|
|
self.score = self.results_mang.score(objective_function) |
194
|
|
|
|
195
|
|
|
# loop to initialize N positions |
196
|
|
|
for init_pos, nth_iter in zip(self.init_positions, range(n_iter)): |
197
|
|
|
self._early_stop() |
198
|
|
|
if self.stop: |
199
|
|
|
break |
200
|
|
|
self._initialization(init_pos, nth_iter) |
201
|
|
|
|
202
|
|
|
self.finish_initialization() |
203
|
|
|
|
204
|
|
|
# loop to do the iterations |
205
|
|
|
for nth_iter in range(len(self.init_positions), n_iter): |
206
|
|
|
self._early_stop() |
207
|
|
|
if self.stop: |
208
|
|
|
break |
209
|
|
|
self._iteration(nth_iter) |
210
|
|
|
|
211
|
|
|
self.results = pd.DataFrame(self.results_mang.results_list) |
212
|
|
|
|
213
|
|
|
self.best_score = self.p_bar.score_best |
214
|
|
|
self.best_value = self.conv.position2value(self.p_bar.pos_best) |
215
|
|
|
self.best_para = self.conv.value2para(self.best_value) |
216
|
|
|
|
217
|
|
|
self.results["eval_time"] = self.eval_times |
218
|
|
|
self.results["iter_time"] = self.iter_times |
219
|
|
|
|
220
|
|
|
if memory is not False: |
221
|
|
|
self.memory_dict = mem.memory_dict |
|
|
|
|
222
|
|
|
else: |
223
|
|
|
self.memory_dict = {} |
224
|
|
|
|
225
|
|
|
self.p_bar.close() |
226
|
|
|
|
227
|
|
|
self.print_info( |
228
|
|
|
verbosity, |
229
|
|
|
self.objective_function, |
230
|
|
|
self.best_score, |
231
|
|
|
self.best_para, |
232
|
|
|
self.eval_times, |
233
|
|
|
self.iter_times, |
234
|
|
|
self.n_iter, |
235
|
|
|
) |
236
|
|
|
|