def testL2RegularizerWithScope(self):
with self.test_session():
shape = [5, 5, 5]
num_elem = 5 * 5 * 5
tensor = tf.constant(1.0, shape=shape)
loss = losses.l2_regularizer(scope='L2')(tensor)
self.assertEquals(loss.op.name, 'L2/value')
self.assertAlmostEqual(loss.eval(), num_elem / 2, 5)
def testL2RegularizerWithWeight(self):
with self.test_session():
shape = [5, 5, 5]
num_elem = 5 * 5 * 5
tensor = tf.constant(1.0, shape=shape)
weight = 0.01
loss = losses.l2_regularizer(weight)(tensor)
self.assertEquals(loss.op.name, 'L2Regularizer/value')
self.assertAlmostEqual(loss.eval(), num_elem * weight / 2, 5)
def fc(inputs,
num_units_out,
activation=tf.nn.relu,
stddev=0.01,
bias=0.0,
weight_decay=0,
batch_norm_params=None,
is_training=True,
trainable=True,
restore=True,
scope=None,
reuse=None):
"""Adds a fully connected layer followed by an optional batch_norm layer.
FC creates a variable called 'weights', representing the fully connected
weight matrix, that is multiplied by the input. If `batch_norm` is None, a
second variable called 'biases' is added to the result of the initial
vector-matrix multiplication.
Args:
inputs: a [B x N] tensor where B is the batch size and N is the number of
input units in the layer.
num_units_out: the number of output units in the layer.
activation: activation function.
stddev: the standard deviation for the weights.
bias: the initial value of the biases.
weight_decay: the weight decay.
batch_norm_params: parameters for the batch_norm. If is None don't use it.
is_training: whether or not the model is in training mode.
trainable: whether or not the variables should be trainable or not.
restore: whether or not the variables should be marked for restore.
scope: Optional scope for variable_scope.
reuse: whether or not the layer and its variables should be reused. To be
able to reuse the layer scope must be given.
Returns:
the tensor variable representing the result of the series of operations.
"""
with tf.variable_scope(scope, 'FC', [inputs], reuse=reuse):
num_units_in = inputs.get_shape()[1]
weights_shape = [num_units_in, num_units_out]
weights_initializer = tf.truncated_normal_initializer(stddev=stddev)
l2_regularizer = None
if weight_decay and weight_decay > 0:
l2_regularizer = losses.l2_regularizer(weight_decay)
weights = variables.variable('weights',
shape=weights_shape,
initializer=weights_initializer,
regularizer=l2_regularizer,
trainable=trainable,
restore=restore)
if batch_norm_params is not None:
outputs = tf.matmul(inputs, weights)
with scopes.arg_scope([batch_norm],
is_training=is_training,
trainable=trainable,
restore=restore):
outputs = batch_norm(outputs, **batch_norm_params)
else:
bias_shape = [
num_units_out,
]
bias_initializer = tf.constant_initializer(bias)
biases = variables.variable('biases',
shape=bias_shape,
initializer=bias_initializer,
trainable=trainable,
restore=restore)
outputs = tf.nn.xw_plus_b(inputs, weights, biases)
if activation:
outputs = activation(outputs)
return outputs
def conv2d(inputs,
num_filters_out,
kernel_size,
stride=1,
padding='SAME',
activation=tf.nn.relu,
stddev=0.01,
bias=0.0,
weight_decay=0,
batch_norm_params=None,
is_training=True,
trainable=True,
restore=True,
scope=None,
reuse=None):
"""Adds a 2D convolution followed by an optional batch_norm layer.
conv2d creates a variable called 'weights', representing the convolutional
kernel, that is convolved with the input. If `batch_norm_params` is None, a
second variable called 'biases' is added to the result of the convolution
operation.
Args:
inputs: a tensor of size [batch_size, height, width, channels].
num_filters_out: the number of output filters.
kernel_size: a list of length 2: [kernel_height, kernel_width] of
of the filters. Can be an int if both values are the same.
stride: a list of length 2: [stride_height, stride_width].
Can be an int if both strides are the same. Note that presently
both strides must have the same value.
padding: one of 'VALID' or 'SAME'.
activation: activation function.
stddev: standard deviation of the truncated guassian weight distribution.
bias: the initial value of the biases.
weight_decay: the weight decay.
batch_norm_params: parameters for the batch_norm. If is None don't use it.
is_training: whether or not the model is in training mode.
trainable: whether or not the variables should be trainable or not.
restore: whether or not the variables should be marked for restore.
scope: Optional scope for variable_scope.
reuse: whether or not the layer and its variables should be reused. To be
able to reuse the layer scope must be given.
Returns:
a tensor representing the output of the operation.
"""
with tf.variable_scope(scope, 'Conv', [inputs], reuse=reuse):
kernel_h, kernel_w = _two_element_tuple(kernel_size)
stride_h, stride_w = _two_element_tuple(stride)
num_filters_in = inputs.get_shape()[-1]
weights_shape = [kernel_h, kernel_w, num_filters_in, num_filters_out]
weights_initializer = tf.truncated_normal_initializer(stddev=stddev)
l2_regularizer = None
if weight_decay and weight_decay > 0:
l2_regularizer = losses.l2_regularizer(weight_decay)
weights = variables.variable('weights',
shape=weights_shape,
initializer=weights_initializer,
regularizer=l2_regularizer,
trainable=trainable,
restore=restore)
conv = tf.nn.conv2d(inputs,
weights, [1, stride_h, stride_w, 1],
padding=padding)
if batch_norm_params is not None:
with scopes.arg_scope([batch_norm],
is_training=is_training,
trainable=trainable,
restore=restore):
outputs = batch_norm(conv, **batch_norm_params)
else:
bias_shape = [
num_filters_out,
]
bias_initializer = tf.constant_initializer(bias)
biases = variables.variable('biases',
shape=bias_shape,
initializer=bias_initializer,
trainable=trainable,
restore=restore)
outputs = tf.nn.bias_add(conv, biases)
if activation:
outputs = activation(outputs)
return outputs