DCRNN/model/tf_model_supervisor.py

283 lines
12 KiB
Python

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import json
import math
import numpy as np
import os
import sys
import tensorflow as tf
import time
from lib import log_helper
from lib import metrics
from lib import tf_utils
from lib import utils
from lib.utils import StandardScaler
from model.tf_model import TFModel
class TFModelSupervisor(object):
"""
Base supervisor for tensorflow models for traffic forecasting.
"""
def __init__(self, config, df_data, **kwargs):
self._config = dict(config)
self._epoch = 0
# logging.
self._init_logging()
self._logger.info(config)
# Data preparation
test_ratio = self._get_config('test_ratio')
validation_ratio = self._get_config('validation_ratio')
self._df_train, self._df_val, self._df_test = utils.train_val_test_split_df(df_data, val_ratio=validation_ratio,
test_ratio=test_ratio)
self._scaler = StandardScaler(mean=self._df_train.values.mean(), std=self._df_train.values.std())
self._x_train, self._y_train, self._x_val, self._y_val, self._x_test, self._y_test = self._prepare_train_val_test_data()
self._eval_dfs = self._prepare_eval_df()
# Build models.
self._train_model, self._val_model, self._test_model = self._build_train_val_test_models()
# Log model statistics.
total_trainable_parameter = tf_utils.get_total_trainable_parameter_size()
self._logger.info('Total number of trainable parameters: %d' % total_trainable_parameter)
for var in tf.global_variables():
self._logger.debug('%s, %s' % (var.name, var.get_shape()))
def _get_config(self, key, use_default=True):
default_config = {
'add_day_in_week': False,
'add_time_in_day': True,
'dropout': 0.,
'batch_size': 64,
'horizon': 12,
'learning_rate': 1e-3,
'lr_decay': 0.1,
'lr_decay_epoch': 50,
'lr_decay_interval': 10,
'max_to_keep': 100,
'min_learning_rate': 2e-6,
'null_val': 0.,
'output_type': 'range',
'patience': 20,
'save_model': 1,
'seq_len': 12,
'test_batch_size': 1,
'test_every_n_epochs': 10,
'test_ratio': 0.2,
'use_cpu_only': False,
'validation_ratio': 0.1,
'verbose': 0,
}
value = self._config.get(key)
if value is None and use_default:
value = default_config.get(key)
return value
def _init_logging(self):
base_dir = self._get_config('base_dir')
log_dir = self._get_config('log_dir')
if log_dir is None:
run_id = self._generate_run_id(self._config)
log_dir = os.path.join(base_dir, run_id)
if not os.path.exists(log_dir):
os.makedirs(log_dir)
else:
run_id = os.path.basename(os.path.normpath(log_dir))
self._log_dir = log_dir
self._logger = log_helper.get_logger(self._log_dir, run_id)
self._writer = tf.summary.FileWriter(self._log_dir)
def train(self, sess, **kwargs):
history = []
min_val_loss = float('inf')
wait = 0
epochs = self._get_config('epochs')
initial_lr = self._get_config('learning_rate')
min_learning_rate = self._get_config('min_learning_rate')
lr_decay_epoch = self._get_config('lr_decay_epoch')
lr_decay = self._get_config('lr_decay')
lr_decay_interval = self._get_config('lr_decay_interval')
patience = self._get_config('patience')
test_every_n_epochs = self._get_config('test_every_n_epochs')
save_model = self._get_config('save_model')
max_to_keep = self._get_config('max_to_keep')
saver = tf.train.Saver(tf.global_variables(), max_to_keep=max_to_keep)
model_filename = self._get_config('model_filename')
if model_filename is not None:
saver.restore(sess, model_filename)
self._train_model.set_lr(sess, self._get_config('learning_rate'))
self._epoch = self._get_config('epoch') + 1
else:
sess.run(tf.global_variables_initializer())
while self._epoch <= epochs:
# Learning rate schedule.
new_lr = self.calculate_scheduled_lr(initial_lr, epoch=self._epoch,
lr_decay=lr_decay, lr_decay_epoch=lr_decay_epoch,
lr_decay_interval=lr_decay_interval,
min_lr=min_learning_rate)
if new_lr != initial_lr:
self._logger.info('Updating learning rate to: %.6f' % new_lr)
self._train_model.set_lr(sess=sess, lr=new_lr)
sys.stdout.flush()
start_time = time.time()
train_results = TFModel.run_epoch(sess, self._train_model,
inputs=self._x_train, labels=self._y_train,
train_op=self._train_model.train_op, writer=self._writer)
train_loss, train_mae = train_results['loss'], train_results['mae']
if train_loss > 1e5:
self._logger.warn('Gradient explosion detected. Ending...')
break
global_step = sess.run(tf.train.get_or_create_global_step())
# Compute validation error.
val_results = TFModel.run_epoch(sess, self._val_model, inputs=self._x_val, labels=self._y_val,
train_op=None)
val_loss, val_mae = val_results['loss'], val_results['mae']
tf_utils.add_simple_summary(self._writer,
['loss/train_loss', 'metric/train_mae', 'loss/val_loss', 'metric/val_mae'],
[train_loss, train_mae, val_loss, val_mae], global_step=global_step)
end_time = time.time()
message = 'Epoch %d (%d) train_loss: %.4f, train_mae: %.4f, val_loss: %.4f, val_mae: %.4f %ds' % (
self._epoch, global_step, train_loss, train_mae, val_loss, val_mae, (end_time - start_time))
self._logger.info(message)
if self._epoch % test_every_n_epochs == test_every_n_epochs - 1:
self.test_and_write_result(sess=sess, global_step=global_step, epoch=self._epoch)
if val_loss <= min_val_loss:
wait = 0
if save_model > 0:
model_filename = self.save_model(sess, saver, val_loss)
self._logger.info(
'Val loss decrease from %.4f to %.4f, saving to %s' % (min_val_loss, val_loss, model_filename))
min_val_loss = val_loss
else:
wait += 1
if wait > patience:
self._logger.warn('Early stopping at epoch: %d' % self._epoch)
break
history.append(val_mae)
# Increases epoch.
self._epoch += 1
sys.stdout.flush()
return np.min(history)
@staticmethod
def calculate_scheduled_lr(initial_lr, epoch, lr_decay, lr_decay_epoch, lr_decay_interval,
min_lr=1e-6):
decay_factor = int(math.ceil((epoch - lr_decay_epoch) / float(lr_decay_interval)))
new_lr = initial_lr * lr_decay ** max(0, decay_factor)
new_lr = max(min_lr, new_lr)
return new_lr
@staticmethod
def _generate_run_id(config):
raise NotImplementedError
@staticmethod
def _get_config_filename(epoch):
return 'config_%02d.json' % epoch
def restore(self, sess, config):
"""
Restore from saved model.
:param sess:
:param config:
:return:
"""
model_filename = config['model_filename']
max_to_keep = self._get_config('max_to_keep')
saver = tf.train.Saver(tf.global_variables(), max_to_keep=max_to_keep)
saver.restore(sess, model_filename)
def save_model(self, sess, saver, val_loss):
config_filename = TFModelSupervisor._get_config_filename(self._epoch)
config = dict(self._config)
global_step = sess.run(tf.train.get_or_create_global_step())
config['epoch'] = self._epoch
config['global_step'] = global_step
config['log_dir'] = self._log_dir
config['model_filename'] = saver.save(sess, os.path.join(self._log_dir, 'models-%.4f' % val_loss),
global_step=global_step, write_meta_graph=False)
with open(os.path.join(self._log_dir, config_filename), 'w') as f:
json.dump(config, f)
return config['model_filename']
def test_and_write_result(self, sess, global_step, **kwargs):
null_val = self._config.get('null_val')
start_time = time.time()
test_results = TFModel.run_epoch(sess, self._test_model, self._x_test, self._y_test, return_output=True,
train_op=None)
# y_preds: a list of (batch_size, horizon, num_nodes, output_dim)
test_loss, y_preds = test_results['loss'], test_results['outputs']
tf_utils.add_simple_summary(self._writer, ['loss/test_loss'], [test_loss], global_step=global_step)
# Reshapes to (batch_size, epoch_size, horizon, num_node)
df_preds = self._convert_model_outputs_to_eval_df(y_preds)
for horizon_i in df_preds:
df_pred = df_preds[horizon_i]
df_test = self._eval_dfs[horizon_i]
mae, mape, rmse = metrics.calculate_metrics(df_pred, df_test, null_val)
tf_utils.add_simple_summary(self._writer,
['%s_%d' % (item, horizon_i + 1) for item in
['metric/rmse', 'metric/mape', 'metric/mae']],
[rmse, mape, mae],
global_step=global_step)
end_time = time.time()
message = 'Horizon %d, mape:%.4f, rmse:%.4f, mae:%.4f, %ds' % (
horizon_i + 1, mape, rmse, mae, end_time - start_time)
self._logger.info(message)
start_time = end_time
return df_preds
def _prepare_train_val_test_data(self):
"""
Prepare data for train, val and test.
:return:
"""
raise NotImplementedError
def _prepare_eval_df(self):
horizon = self._get_config('horizon')
seq_len = self._get_config('seq_len')
# y_test: (epoch_size, batch_size, ...)
n_test_samples = np.prod(self._y_test.shape[:2])
eval_dfs = {}
for horizon_i in range(horizon):
eval_dfs[horizon_i] = self._df_test[seq_len + horizon_i: seq_len + horizon_i + n_test_samples]
return eval_dfs
def _build_train_val_test_models(self):
"""
Buids models for train, val and test.
:return:
"""
raise NotImplementedError
def _convert_model_outputs_to_eval_df(self, y_preds):
"""
Convert the outputs to a dict, with key: horizon, value: the corresponding dataframe.
:param y_preds:
:return:
"""
raise NotImplementedError
@property
def log_dir(self):
return self._log_dir