在一些post上遵循有关使用 AlexNet 对猫和狗进行分类的示例时，我陷入了这个导入错误：
Traceback (most recent call last):
File "C:\Users\Gsum\Desktop\Asirra 개 고양이\asirra-dogs-cats-classification-master\learning\optimizers.py", line 5, in <module>
from learning.utils import plot_learning_curve
ImportError: No module named 'learning'
我一直在寻找名称类似于学习或学习的模块，其中包含“plot_learning_curve”函数。
任何人知道哪个库包含绘图学习曲线函数，我将不胜感激。
这是我的代码：
import os
import time
from abc import abstractmethod
import tensorflow as tf
from learning.utils import plot_learning_curve
class Optimizer(object):
"""Base class for gradient-based optimization algorithms."""
def __init__(self, model, train_set, evaluator, val_set=None, **kwargs):
"""
Optimizer initializer.
:param model: ConvNet, the model to be learned.
:param train_set: DataSet, training set to be used.
:param evaluator: Evaluator, for computing performance scores during training.
:param val_set: DataSet, validation set to be used, which can be None if not used.
:param kwargs: dict, extra arguments containing training hyperparameters.
- batch_size: int, batch size for each iteration.
- num_epochs: int, total number of epochs for training.
- init_learning_rate: float, initial learning rate.
"""
self.model = model
self.train_set = train_set
self.evaluator = evaluator
self.val_set = val_set
# Training hyperparameters
self.batch_size = kwargs.pop('batch_size', 256)
self.num_epochs = kwargs.pop('num_epochs', 320)
self.init_learning_rate = kwargs.pop('init_learning_rate', 0.01)
self.learning_rate_placeholder = tf.placeholder(tf.float32) # Placeholder for current learning rate
self.optimize = self._optimize_op()
self._reset()
def _reset(self):
"""Reset some variables."""
self.curr_epoch = 1
self.num_bad_epochs = 0 # number of bad epochs, where the model is updated without improvement.
self.best_score = self.evaluator.worst_score # initialize best score with the worst one
self.curr_learning_rate = self.init_learning_rate # current learning rate
@abstractmethod
def _optimize_op(self, **kwargs):
"""
tf.train.Optimizer.minimize Op for a gradient update.
This should be implemented, and should not be called manually.
"""
pass
@abstractmethod
def _update_learning_rate(self, **kwargs):
"""
Update current learning rate (if needed) on every epoch, by its own schedule.
This should be implemented, and should not be called manually.
"""
pass
def _step(self, sess, **kwargs):
"""
Make a single gradient update and return its results.
This should not be called manually.
:param sess: tf.Session.
:param kwargs: dict, extra arguments containing training hyperparameters.
- augment_train: bool, whether to perform augmentation for training.
:return loss: float, loss value for the single iteration step.
y_true: np.ndarray, true label from the training set.
y_pred: np.ndarray, predicted label from the model.
"""
augment_train = kwargs.pop('augment_train', True)
# Sample a single batch
X, y_true = self.train_set.next_batch(self.batch_size, shuffle=True,
augment=augment_train, is_train=True)
# Compute the loss and make update
_, loss, y_pred = \
sess.run([self.optimize, self.model.loss, self.model.pred],
feed_dict={self.model.X: X, self.model.y: y_true,
self.model.is_train: True,
self.learning_rate_placeholder: self.curr_learning_rate})
return loss, y_true, y_pred
def train(self, sess, save_dir='/tmp', details=False, verbose=True, **kwargs):
"""
Run optimizer to train the model.
:param sess: tf.Session.
:param save_dir: str, the directory to save the learned weights of the model.
:param details: bool, whether to return detailed results.
:param verbose: bool, whether to print details during training.
:param kwargs: dict, extra arguments containing training hyperparameters.
:return train_results: dict, containing detailed results of training.
"""
saver = tf.train.Saver()
sess.run(tf.global_variables_initializer()) # initialize all weights
train_results = dict() # dictionary to contain training(, evaluation) results and details
train_size = self.train_set.num_examples
num_steps_per_epoch = train_size // self.batch_size
num_steps = self.num_epochs * num_steps_per_epoch
if verbose:
print('Running training loop...')
print('Number of training iterations: {}'.format(num_steps))
step_losses, step_scores, eval_scores = [], [], []
start_time = time.time()
# Start training loop
for i in range(num_steps):
# Perform a gradient update from a single minibatch
step_loss, step_y_true, step_y_pred = self._step(sess, **kwargs)
step_losses.append(step_loss)
# Perform evaluation in the end of each epoch
if (i+1) % num_steps_per_epoch == 0:
# Evaluate model with current minibatch, from training set
step_score = self.evaluator.score(step_y_true, step_y_pred)
step_scores.append(step_score)
# If validation set is initially given, use it for evaluation
if self.val_set is not None:
# Evaluate model with the validation set
eval_y_pred = self.model.predict(sess, self.val_set, verbose=False, **kwargs)
eval_score = self.evaluator.score(self.val_set.labels, eval_y_pred)
eval_scores.append(eval_score)
if verbose:
# Print intermediate results
print('[epoch {}]\tloss: {:.6f} |Train score: {:.6f} |Eval score: {:.6f} |lr: {:.6f}'\
.format(self.curr_epoch, step_loss, step_score, eval_score, self.curr_learning_rate))
# Plot intermediate results
plot_learning_curve(-1, step_losses, step_scores, eval_scores=eval_scores,
mode=self.evaluator.mode, img_dir=save_dir)
curr_score = eval_score
# else, just use results from current minibatch for evaluation
else:
if verbose:
# Print intermediate results
print('[epoch {}]\tloss: {} |Train score: {:.6f} |lr: {:.6f}'\
.format(self.curr_epoch, step_loss, step_score, self.curr_learning_rate))
# Plot intermediate results
plot_learning_curve(-1, step_losses, step_scores, eval_scores=None,
mode=self.evaluator.mode, img_dir=save_dir)
curr_score = step_score
# Keep track of the current best model,
# by comparing current score and the best score
if self.evaluator.is_better(curr_score, self.best_score, **kwargs):
self.best_score = curr_score
self.num_bad_epochs = 0
saver.save(sess, os.path.join(save_dir, 'model.ckpt')) # save current weights
else:
self.num_bad_epochs += 1
self._update_learning_rate(**kwargs)
self.curr_epoch += 1
if verbose:
print('Total training time(sec): {}'.format(time.time() - start_time))
print('Best {} score: {}'.format('evaluation' if eval else 'training',
self.best_score))
print('Done.')
if details:
# Store training results in a dictionary
train_results['step_losses'] = step_losses # (num_iterations)
train_results['step_scores'] = step_scores # (num_epochs)
if self.val_set is not None:
train_results['eval_scores'] = eval_scores # (num_epochs)
return train_results
class MomentumOptimizer(Optimizer):
"""Gradient descent optimizer, with Momentum algorithm."""
def _optimize_op(self, **kwargs):
"""
tf.train.MomentumOptimizer.minimize Op for a gradient update.
:param kwargs: dict, extra arguments for optimizer.
- momentum: float, the momentum coefficient.
:return tf.Operation.
"""
momentum = kwargs.pop('momentum', 0.9)
update_vars = tf.trainable_variables()
return tf.train.MomentumOptimizer(self.learning_rate_placeholder, momentum, use_nesterov=False)\
.minimize(self.model.loss, var_list=update_vars)
def _update_learning_rate(self, **kwargs):
"""
Update current learning rate, when evaluation score plateaus.
:param kwargs: dict, extra arguments for learning rate scheduling.
- learning_rate_patience: int, number of epochs with no improvement
after which learning rate will be reduced.
- learning_rate_decay: float, factor by which the learning rate will be updated.
- eps: float, if the difference between new and old learning rate is smaller than eps,
the update is ignored.
"""
learning_rate_patience = kwargs.pop('learning_rate_patience', 10)
learning_rate_decay = kwargs.pop('learning_rate_decay', 0.1)
eps = kwargs.pop('eps', 1e-8)
if self.num_bad_epochs > learning_rate_patience:
new_learning_rate = self.curr_learning_rate * learning_rate_decay
# Decay learning rate only when the difference is higher than epsilon.
if self.curr_learning_rate - new_learning_rate > eps:
self.curr_learning_rate = new_learning_rate
self.num_bad_epochs = 0
模块：mlxtend
从mlxtend.plotting导入plot_learning_curves