def loss(logits, labels):
"""Add L2Loss to all the trainable variables.
Add summary for for "Loss" and "Loss/avg".
Args:
logits: Logits from inference().
labels: Labels from distorted_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(labels=labels, logits=logits, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses', cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
python类add_n()的实例源码
def loss(logits, labels):
"""Add L2Loss to all the trainable variables.
Add summary for for "Loss" and "Loss/avg".
Args:
logits: Logits from inference().
labels: Labels from distorted_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(labels=labels, logits=logits, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses', cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
def loss(c_fuse, s_fuse, labels):
"""Add L2Loss to all the trainable variables.
Add summary for "Loss" and "Loss/avg".
Args:
c_fuse: Contours output map from inference().
s_fuse: Segments output map from inference().
labels: Labels from distorted_inputs or inputs().
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
# Split the labels tensor into contours and segments image tensors
# Each has shape [FLAGS.batch_size, 696, 520, 1]
contours_labels, segments_labels = tf.split(labels, 2, 3)
_add_cross_entropy(contours_labels, c_fuse, 'c')
_add_cross_entropy(segments_labels, s_fuse, 's')
return tf.add_n(tf.get_collection('losses'), name='total_loss')
def _get_loss(self,labels):
with tf.name_scope("Loss"):
"""
with tf.name_scope("logloss"):
logit = tf.squeeze(tf.nn.sigmoid(self.logit))
self.loss = tf.reduce_mean(self._logloss(labels, logit))
"""
with tf.name_scope("L2_loss"):
if self.flags.lambdax:
lambdax = self.flags.lambdax
else:
lambdax = 0
self.l2loss = lambdax*tf.add_n(tf.get_collection(tf.GraphKeys.REGULARIZATION_LOSSES))
with tf.name_scope("dice_coef"):
#yp_label = tf.cast(logit>self.flags.threshold, tf.float32)
logit = tf.squeeze(self.logit)
self.acc = tf.reduce_mean(self._dice_coef(labels,logit))
self.metric = "dice_coef"
self.loss = -self.acc
with tf.name_scope("summary"):
if self.flags.visualize:
tf.summary.scalar(name='dice coef', tensor=self.acc, collections=[tf.GraphKeys.SCALARS])
a2_transformer_classification.py 文件源码
项目：text_classification
作者: brightmart
项目源码
文件源码
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def loss(self, l2_lambda=0.0001): # 0.001
with tf.name_scope("loss"):
# input: `logits`:[batch_size, num_classes], and `labels`:[batch_size]
# output: A 1-D `Tensor` of length `batch_size` of the same type as `logits` with the softmax cross entropy loss.
losses = tf.nn.sparse_softmax_cross_entropy_with_logits(labels=self.input_y_label,logits=self.logits); # sigmoid_cross_entropy_with_logits.#losses=tf.nn.softmax_cross_entropy_with_logits(labels=self.input_y,logits=self.logits)
# print("1.sparse_softmax_cross_entropy_with_logits.losses:",losses) # shape=(?,)
loss = tf.reduce_mean(losses) # print("2.loss.loss:", loss) #shape=()
l2_losses = tf.add_n([tf.nn.l2_loss(v) for v in tf.trainable_variables() if ('bias' not in v.name ) and ('alpha' not in v.name)]) * l2_lambda
loss = loss + l2_losses
return loss
#def loss_seq2seq(self):
# with tf.variable_scope("loss"):
# losses = tf.nn.sparse_softmax_cross_entropy_with_logits(labels=self.input_y_label, logits=self.logits);#losses:[batch_size,self.decoder_sent_length]
# loss_batch=tf.reduce_sum(losses,axis=1)/self.decoder_sent_length #loss_batch:[batch_size]
# loss=tf.reduce_mean(loss_batch)
# l2_losses = tf.add_n([tf.nn.l2_loss(v) for v in tf.trainable_variables() if 'bias' not in v.name]) * self.l2_lambda
# loss = loss + l2_losses
# return loss
def loss_nce(self,l2_lambda=0.0001): #0.0001-->0.001
"""calculate loss using (NCE)cross entropy here"""
# Compute the average NCE loss for the batch.
# tf.nce_loss automatically draws a new sample of the negative labels each
# time we evaluate the loss.
if self.is_training: #training
#labels=tf.reshape(self.input_y,[-1]) #[batch_size,1]------>[batch_size,]
labels=tf.expand_dims(self.input_y,1) #[batch_size,]----->[batch_size,1]
loss = tf.reduce_mean( #inputs: A `Tensor` of shape `[batch_size, dim]`. The forward activations of the input network.
tf.nn.nce_loss(weights=tf.transpose(self.W_projection),#[hidden_size*2, num_classes]--->[num_classes,hidden_size*2]. nce_weights:A `Tensor` of shape `[num_classes, dim].O.K.
biases=self.b_projection, #[label_size]. nce_biases:A `Tensor` of shape `[num_classes]`.
labels=labels, #[batch_size,1]. train_labels, # A `Tensor` of type `int64` and shape `[batch_size,num_true]`. The target classes.
inputs=self.output_rnn_last,# [batch_size,hidden_size*2] #A `Tensor` of shape `[batch_size, dim]`. The forward activations of the input network.
num_sampled=self.num_sampled, #scalar. 100
num_classes=self.num_classes,partition_strategy="div")) #scalar. 1999
l2_losses = tf.add_n([tf.nn.l2_loss(v) for v in tf.trainable_variables() if 'bias' not in v.name]) * l2_lambda
loss = loss + l2_losses
return loss
def loss(logits, label_batch):
"""
Add L2Loss to all the trainable variables.
Add summary for "Loss" and "Loss/avg".
Args:
logits -> logits from inference()
label_batch -> 1D tensor of [batch_size]
Rtns:
total_loss -> float tensor
"""
# Calculate the average cross entropy loss across the batch.
label_batch = tf.cast(label_batch,tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(logits,
label_batch,name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses',cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
def tower_loss(name_scope, autoencoder, clips):
# calculate reconstruction loss
rec_loss = tf.reduce_mean(tf.abs(clips-autoencoder.rec_vid))
weight_decay_loss_list = tf.get_collection('losses', name_scope)
weight_decay_loss = 0.0
if len(weight_decay_loss_list) > 0:
weight_decay_loss = tf.add_n(weight_decay_loss_list)
tf.add_to_collection('losses', rec_loss)
losses = tf.get_collection('losses', name_scope)
# Calculate the total loss for the current tower.
total_loss = tf.add_n(losses, name='total_loss')
return total_loss, rec_loss, weight_decay_loss
def tower_loss(name_scope, mfb, use_pretrained_encoder, encoder_gradient_ratio=1.0):
# get reconstruction and ground truth
ac_loss = mfb.ac_loss
weight_decay_loss_list = tf.get_collection('losses', name_scope)
if use_pretrained_encoder:
if encoder_gradient_ratio == 0.0:
weight_decay_loss_list = [var for var in weight_decay_loss_list \
if 'c3d' not in var.name and 'mapping' not in var.name]
weight_decay_loss = 0.0
if len(weight_decay_loss_list) > 0:
weight_decay_loss = tf.add_n(weight_decay_loss_list)
total_loss = weight_decay_loss * 100 + ac_loss
return total_loss, ac_loss, weight_decay_loss
def _loss_shared(logits, labels):
"""Add L2Loss to all the trainable variables.
Add summary for "Loss" and "Loss/avg".
Args:
logits: Logits from inference().
labels: Labels from distorted_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits, labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses', cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
def inference(images, batch_size, train):
"""Build the ocr model.
Args:
images: Images returned from distorted_inputs() or inputs().
Returns:
Logits.
"""
features, timesteps = convolutional_layers(images, batch_size, train)
logits = get_lstm_layers(features, timesteps, batch_size)
return logits, timesteps
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
# return tf.add_n(tf.get_collection('losses'), name='total_loss')
def __init__(self, ob_dim, ac_dim): #pylint: disable=W0613
X = tf.placeholder(tf.float32, shape=[None, ob_dim*2+ac_dim*2+2]) # batch of observations
vtarg_n = tf.placeholder(tf.float32, shape=[None], name='vtarg')
wd_dict = {}
h1 = tf.nn.elu(dense(X, 64, "h1", weight_init=U.normc_initializer(1.0), bias_init=0, weight_loss_dict=wd_dict))
h2 = tf.nn.elu(dense(h1, 64, "h2", weight_init=U.normc_initializer(1.0), bias_init=0, weight_loss_dict=wd_dict))
vpred_n = dense(h2, 1, "hfinal", weight_init=U.normc_initializer(1.0), bias_init=0, weight_loss_dict=wd_dict)[:,0]
sample_vpred_n = vpred_n + tf.random_normal(tf.shape(vpred_n))
wd_loss = tf.get_collection("vf_losses", None)
loss = U.mean(tf.square(vpred_n - vtarg_n)) + tf.add_n(wd_loss)
loss_sampled = U.mean(tf.square(vpred_n - tf.stop_gradient(sample_vpred_n)))
self._predict = U.function([X], vpred_n)
optim = kfac.KfacOptimizer(learning_rate=0.001, cold_lr=0.001*(1-0.9), momentum=0.9, \
clip_kl=0.3, epsilon=0.1, stats_decay=0.95, \
async=1, kfac_update=2, cold_iter=50, \
weight_decay_dict=wd_dict, max_grad_norm=None)
vf_var_list = []
for var in tf.trainable_variables():
if "vf" in var.name:
vf_var_list.append(var)
update_op, self.q_runner = optim.minimize(loss, loss_sampled, var_list=vf_var_list)
self.do_update = U.function([X, vtarg_n], update_op) #pylint: disable=E1101
U.initialize() # Initialize uninitialized TF variables
def loss(self, predictions, real_values):
"""Return the loss operation between predictions and real_values.
Add L2 weight decay term if any.
Args:
predictions: predicted values
real_values: real values
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# 1/2n \sum^{n}_{i=i}{(x_i - x'_i)^2}
mse = tf.divide(
tf.reduce_mean(
tf.square(tf.subtract(predictions, real_values))),
2.,
name="mse")
tf.add_to_collection(LOSSES, mse)
# mse + weight_decay per layer
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
def loss(self, logits, labels):
"""Add L2Loss to all the trainable variables.
Args:
logits: Logits from get().
labels: Labels from train_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits=logits, labels=labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(
cross_entropy, name='cross_entropy')
tf.add_to_collection(LOSSES, cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
def loss(self, logits, labels):
"""Add L2Loss to all the trainable variables.
Args:
logits: Logits from get().
labels: Labels from train_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits=logits, labels=labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(
cross_entropy, name='cross_entropy')
tf.add_to_collection(LOSSES, cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
def loss(self, logits, labels):
"""Add L2Loss to all the trainable variables.
Args:
logits: Logits from get().
labels: Labels from train_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits=logits, labels=labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(
cross_entropy, name='cross_entropy')
tf.add_to_collection(LOSSES, cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
def loss(self, logits, labels):
"""Add L2Loss to all the trainable variables.
Args:
logits: Logits from get().
labels: Labels from train_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits=logits, labels=labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(
cross_entropy, name='cross_entropy')
tf.add_to_collection(LOSSES, cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
def loss(self, logits, labels):
"""Add L2Loss to all the trainable variables.
Args:
logits: Logits from get().
labels: Labels from train_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits=logits, labels=labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(
cross_entropy, name='cross_entropy')
tf.add_to_collection(LOSSES, cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
def loss(self, logits, labels):
"""Add L2Loss to all the trainable variables.
Args:
logits: Logits from get().
labels: Labels from train_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits=logits, labels=labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(
cross_entropy, name='cross_entropy')
tf.add_to_collection(LOSSES, cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
def loss(self, logits, labels):
"""Add L2Loss to all the trainable variables.
Args:
logits: Logits from get().
labels: Labels from train_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits=logits, labels=labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(
cross_entropy, name='cross_entropy')
tf.add_to_collection(LOSSES, cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
def loss(self, logits, labels):
"""Add L2Loss to all the trainable variables.
Args:
logits: Logits from get().
labels: Labels from train_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
with tf.variable_scope('loss'):
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits=logits, labels=labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(
cross_entropy, name='cross_entropy')
tf.add_to_collection(LOSSES, cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
error = tf.add_n(tf.get_collection(LOSSES), name='total_loss')
return error
SENN.py 文件源码
项目：Multi-channel-speech-extraction-using-DNN
作者: zhr1201
项目源码
文件源码
阅读 32
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def loss(self, inf_targets, inf_vads, targets, vads, mtl_fac):
'''
Loss definition
Only speech inference loss is defined and work quite well
Add VAD cross entropy loss if you want
'''
loss_v1 = tf.nn.l2_loss(inf_targets - targets) / self.batch_size
loss_o = loss_v1
reg_loss = tf.get_collection(tf.GraphKeys.REGULARIZATION_LOSSES)
# ipdb.set_trace()
loss_v = loss_o + tf.add_n(reg_loss)
tf.scalar_summary('loss', loss_v)
# loss_merge = tf.cond(
# is_val, lambda: tf.scalar_summary('val_loss_batch', loss_v),
# lambda: tf.scalar_summary('loss', loss_v))
return loss_v, loss_o
# return tf.reduce_mean(tf.nn.l2_loss(inf_targets - targets))
def loss(logits, labels):
"""Add L2Loss to all the trainable variables.
Add summary for for "Loss" and "Loss/avg".
Args:
logits: Logits from inference().
labels: Labels from distorted_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits, labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses', cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
def loss(logits, labels):
"""Add L2Loss to all the trainable variables.
Add summary for for "Loss" and "Loss/avg".
Args:
logits: Logits from inference().
labels: Labels from distorted_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits, labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses', cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
def loss(logits, labels):
"""Add L2Loss to all the trainable variables.
Add summary for for "Loss" and "Loss/avg".
Args:
logits: Logits from inference().
labels: Labels from distorted_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits, labels, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses', cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
def loss(logits, labels):
"""Add L2Loss to all the trainable variables.
Add summary for "Loss" and "Loss/avg".
Args:
logits: Logits from inference().
labels: Labels from distorted_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
labels=labels, logits=logits, name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses', cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
def average_gradients(tower_grads):
"""Calculate the average gradient for each shared variable across all towers.
Note that this function provides a synchronization point across all towers.
Args:
tower_grads: List of lists of (gradient, variable) tuples. The outer list
is over individual gradients. The inner list is over the gradient
calculation for each tower.
Returns:
List of pairs of (gradient, variable) where the gradient has been averaged
across all towers.
"""
average_grads = []
for single_grads in zip(*tower_grads):
grads = [g for g, _ in single_grads]
grad = tf.add_n(grads)
grad = tf.multiply(grad, 1.0/len(grads))
v = single_grads[0][1]
grad_and_var = (grad, v)
average_grads.append(grad_and_var)
return average_grads
def average_gradients(tower_grads):
"""Calculate the average gradient for each shared variable across all towers.
Note that this function provides a synchronization point across all towers.
Args:
tower_grads: List of lists of (gradient, variable) tuples. The outer list
is over individual gradients. The inner list is over the gradient
calculation for each tower.
Returns:
List of pairs of (gradient, variable) where the gradient has been averaged
across all towers.
"""
average_grads = []
for single_grads in zip(*tower_grads):
grads = [g for g, _ in single_grads]
grad = tf.add_n(grads)
grad = tf.multiply(grad, 1.0/len(grads))
v = single_grads[0][1]
grad_and_var = (grad, v)
average_grads.append(grad_and_var)
return average_grads
def average_gradients(tower_grads):
"""Calculate the average gradient for each shared variable across all towers.
Note that this function provides a synchronization point across all towers.
Args:
tower_grads: List of lists of (gradient, variable) tuples. The outer list
is over individual gradients. The inner list is over the gradient
calculation for each tower.
Returns:
List of pairs of (gradient, variable) where the gradient has been averaged
across all towers.
"""
average_grads = []
for single_grads in zip(*tower_grads):
grads = [g for g, _ in single_grads]
grad = tf.add_n(grads)
grad = tf.multiply(grad, 1.0/len(grads))
v = single_grads[0][1]
grad_and_var = (grad, v)
average_grads.append(grad_and_var)
return average_grads
def loss(logits, labels):
"""Add L2Loss to all the trainable variables.
Add summary for "Loss" and "Loss/avg".
Args:
logits: Logits from inference().
labels: Labels from distorted_inputs or inputs(). 1-D tensor
of shape [batch_size]
Returns:
Loss tensor of type float.
"""
# Calculate the average cross entropy loss across the batch.
labels = tf.cast(labels, tf.int64)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
logits,
labels,
name='cross_entropy_per_example')
cross_entropy_mean = tf.reduce_mean(cross_entropy, name='cross_entropy')
tf.add_to_collection('losses', cross_entropy_mean)
# The total loss is defined as the cross entropy loss plus all of the weight
# decay terms (L2 loss).
return tf.add_n(tf.get_collection('losses'), name='total_loss')
