def test_convolutional_layer():
x = tensor.tensor4('x')
num_channels = 4
batch_size = 5
pooling_size = 3
num_filters = 3
filter_size = (3, 3)
activation = Rectifier().apply
conv = ConvolutionalLayer(activation, filter_size, num_filters,
(pooling_size, pooling_size),
num_channels, image_size=(17, 13),
batch_size=batch_size,
weights_init=Constant(1.),
biases_init=Constant(5.))
conv.initialize()
y = conv.apply(x)
func = function([x], y)
x_val = numpy.ones((batch_size, num_channels, 17, 13),
dtype=theano.config.floatX)
assert_allclose(func(x_val), numpy.prod(filter_size) * num_channels *
numpy.ones((batch_size, num_filters, 5, 4)) + 5)
assert_equal(conv.convolution.batch_size, batch_size)
assert_equal(conv.pooling.batch_size, batch_size)
def test_convolutional_layer():
x = tensor.tensor4('x')
num_channels = 4
batch_size = 5
pooling_size = 3
num_filters = 3
filter_size = (3, 3)
activation = Rectifier().apply
conv = ConvolutionalLayer(activation,
filter_size,
num_filters, (pooling_size, pooling_size),
num_channels,
image_size=(17, 13),
weights_init=Constant(1.),
biases_init=Constant(5.))
conv.initialize()
y = conv.apply(x)
func = function([x], y)
x_val = numpy.ones((batch_size, num_channels, 17, 13),
dtype=theano.config.floatX)
assert_allclose(
func(x_val),
numpy.prod(filter_size) * num_channels * numpy.ones(
(batch_size, num_filters, 5, 4)) + 5)
def test_convolutional_layer_use_bias():
act = ConvolutionalLayer(Rectifier().apply, (3, 3),
5, (2, 2),
6,
image_size=(9, 9),
use_bias=False)
act.allocate()
assert not act.convolution.use_bias
assert len(ComputationGraph([act.apply(tensor.tensor4())]).parameters) == 1
def test_convolutional_sequence():
x = tensor.tensor4('x')
num_channels = 4
pooling_size = 3
batch_size = 5
activation = Rectifier().apply
conv = ConvolutionalLayer(activation, (3, 3),
5, (pooling_size, pooling_size),
weights_init=Constant(1.),
biases_init=Constant(5.))
conv2 = ConvolutionalActivation(activation, (2, 2),
4,
weights_init=Constant(1.))
seq = ConvolutionalSequence([conv, conv2],
num_channels,
image_size=(17, 13))
seq.push_allocation_config()
assert conv.num_channels == 4
assert conv2.num_channels == 5
conv2.convolution.use_bias = False
y = seq.apply(x)
seq.initialize()
func = function([x], y)
x_val = numpy.ones((batch_size, 4, 17, 13), dtype=theano.config.floatX)
y_val = (numpy.ones((batch_size, 4, 4, 3)) * (9 * 4 + 5) * 4 * 5)
assert_allclose(func(x_val), y_val)
def main():
initial = numpy.random.normal(0, 0.1, (1, 1, 200, 200))
x = theano.shared(initial)
conv_layer = ConvolutionalLayer(
Rectifier().apply,
(16, 16),
9,
(4, 4),
1
)
conv_layer2 = ConvolutionalLayer(
Rectifier().apply,
(7, 7),
9,
(2, 2),
1
)
con_seq = ConvolutionalSequence([conv_layer], 1,
image_size=(200, 200),
weights_init=IsotropicGaussian(0.1),
biases_init=Constant(0.)
)
con_seq.initialize()
out = con_seq.apply(x)
target_out = out[0, 0, 1, 1]
grad = theano.grad(target_out - .1 * (x ** 2).sum(), x)
updates = {x: x + 5e-1 * grad}
#x.set_value(numpy.ones((1, 1, 200, 200)))
#print theano.function([], out)()
make_step = theano.function([], target_out, updates=updates)
for i in xrange(400):
out_val = make_step()
print i, out_val
image = x.get_value()[0][0]
image = (image - image.mean()) / image.std()
image = numpy.array([image, image, image]).transpose(1, 2, 0)
plt.imshow(numpy.cast['uint8'](image * 65. + 128.), interpolation='none')
plt.show()
def __init__(self,
conv_activations,
num_channels,
image_shape,
filter_sizes,
feature_maps,
pooling_sizes,
top_mlp_activations,
top_mlp_dims,
conv_step=None,
border_mode='valid',
**kwargs):
if conv_step is None:
self.conv_step = (1, 1)
else:
self.conv_step = conv_step
self.num_channels = num_channels
self.image_shape = image_shape
self.top_mlp_activations = top_mlp_activations
self.top_mlp_dims = top_mlp_dims
self.border_mode = border_mode
parameters = zip(conv_activations, filter_sizes, feature_maps,
pooling_sizes)
# Construct convolutional layers with corresponding parameters
self.layers = [
ConvolutionalLayer(filter_size=filter_size,
num_filters=num_filter,
pooling_size=pooling_size,
activation=activation.apply,
conv_step=self.conv_step,
border_mode=self.border_mode,
name='conv_pool_{}'.format(i))
for i, (activation, filter_size, num_filter,
pooling_size) in enumerate(parameters)
]
self.conv_sequence = ConvolutionalSequence(self.layers,
num_channels,
image_size=image_shape)
# Construct a top MLP
self.top_mlp = MLP(top_mlp_activations, top_mlp_dims)
# We need to flatten the output of the last convolutional layer.
# This brick accepts a tensor of dimension (batch_size, ...) and
# returns a matrix (batch_size, features)
self.flattener = Flattener()
application_methods = [
self.conv_sequence.apply, self.flattener.apply, self.top_mlp.apply
]
super(LeNet, self).__init__(application_methods, **kwargs)
def test_border_mode_not_pushed():
layers = [
Convolutional(border_mode='full'),
ConvolutionalActivation(Rectifier().apply),
ConvolutionalActivation(Rectifier().apply, border_mode='valid'),
ConvolutionalLayer(Rectifier().apply, border_mode='full')
]
stack = ConvolutionalSequence(layers)
stack.push_allocation_config()
assert stack.children[0].border_mode == 'full'
assert stack.children[1].border_mode == 'valid'
assert stack.children[2].border_mode == 'valid'
assert stack.children[3].border_mode == 'full'
stack2 = ConvolutionalSequence(layers, border_mode='full')
stack2.push_allocation_config()
assert stack2.children[0].border_mode == 'full'
assert stack2.children[1].border_mode == 'full'
assert stack2.children[2].border_mode == 'full'
assert stack2.children[3].border_mode == 'full'
def test_convolutional_layer_use_bias():
act = ConvolutionalLayer(Rectifier().apply, (3, 3), 5, (2, 2), 6, image_size=(9, 9), use_bias=False)
act.allocate()
assert not act.convolution.use_bias
assert len(ComputationGraph([act.apply(tensor.tensor4())]).parameters) == 1
from blocks.initialization import IsotropicGaussian, Constant, Uniform
from blocks.roles import WEIGHT, FILTER, INPUT
from blocks.graph import ComputationGraph, apply_dropout
batch_size = 128
filter_size = 3
num_filters = 4
initial_weight_std = .01
epochs = 5
x = T.tensor4('features')
y = T.lmatrix('targets')
# Convolutional Layers
conv_layers = [
ConvolutionalLayer(Rectifier().apply, (3, 3), 16, (2, 2), name='l1'),
ConvolutionalLayer(Rectifier().apply, (3, 3), 32, (2, 2), name='l2')
]
convnet = ConvolutionalSequence(conv_layers,
num_channels=1,
image_size=(28, 28),
weights_init=IsotropicGaussian(0.1),
biases_init=Constant(0))
convnet.initialize()
output_dim = np.prod(convnet.get_dim('output'))
print(output_dim)
# Fully connected layers
def run_experiment():
np.random.seed(42)
X = tensor.tensor4('features')
nbr_channels = 3
image_shape = (5, 5)
conv_layers = [
ConvolutionalLayer(
filter_size=(2, 2),
num_filters=10,
activation=Rectifier().apply,
border_mode='valid',
pooling_size=(1, 1),
weights_init=Uniform(width=0.1),
#biases_init=Uniform(width=0.01),
biases_init=Constant(0.0),
name='conv0')
]
conv_sequence = ConvolutionalSequence(conv_layers,
num_channels=nbr_channels,
image_size=image_shape)
#conv_sequence.push_allocation_config()
conv_sequence.initialize()
flattener = Flattener()
conv_output = conv_sequence.apply(X)
y_hat = flattener.apply(conv_output)
# Whatever. Not important since we're not going to actually train anything.
cost = tensor.sqr(y_hat).sum()
#L_grads_method_02 = [tensor.grad(cost, v) for v in VariableFilter(roles=[FILTER, BIAS])(ComputationGraph([y_hat]).variables)]
L_grads_method_02 = [
tensor.grad(cost, v) for v in VariableFilter(
roles=[BIAS])(ComputationGraph([y_hat]).variables)
]
# works on the sum of the gradients in a mini-batch
sum_square_norm_gradients_method_02 = sum(
[tensor.sqr(g).sum() for g in L_grads_method_02])
D_by_layer = get_conv_layers_transformation_roles(
ComputationGraph(conv_output))
individual_sum_square_norm_gradients_method_00 = get_sum_square_norm_gradients_conv_transformations(
D_by_layer, cost)
# why does this thing depend on N again ?
# I don't think I've used a cost that divides by N.
N = 2
Xtrain = np.random.randn(N, nbr_channels, image_shape[0],
image_shape[1]).astype(np.float32)
#Xtrain[1:,:,:,:] = 0.0
Xtrain[:, :, :, :] = 1.0
convolution_filter_variable = VariableFilter(roles=[FILTER])(
ComputationGraph([y_hat]).variables)[0]
convolution_filter_variable_value = convolution_filter_variable.get_value()
convolution_filter_variable_value[:, :, :, :] = 1.0
#convolution_filter_variable_value[0,0,:,:] = 1.0
convolution_filter_variable.set_value(convolution_filter_variable_value)
f = theano.function([X], [
cost, individual_sum_square_norm_gradients_method_00,
sum_square_norm_gradients_method_02
])
[c, v0, gs2] = f(Xtrain)
#print "[c, v0, gs2]"
L_c, L_v0, L_gs2 = ([], [], [])
for n in range(N):
[nc, nv0, ngs2] = f(Xtrain[n, :, :, :].reshape(
(1, Xtrain.shape[1], Xtrain.shape[2], Xtrain.shape[3])))
L_c.append(nc)
L_v0.append(nv0)
L_gs2.append(ngs2)
print "Cost for whole mini-batch in single shot : %f." % c
print "Cost for whole mini-batch accumulated : %f." % sum(L_c)
print ""
print "Square-norm of all gradients for each data point in single shot :"
print v0.reshape((1, -1))
print "Square-norm of all gradients for each data point iteratively :"
print np.array(L_gs2).reshape((1, -1))
print ""
print "Difference max abs : %f." % np.max(np.abs(v0 - np.array(L_gs2)))
print ""
print "Ratios : "
print np.array(L_gs2).reshape((1, -1)) / v0.reshape((1, -1))
# from blocks.bricks.cost import CategoricalCrossEntropy
from blocks.bricks.conv import (ConvolutionalLayer, ConvolutionalSequence,
Flattener)
from blocks.initialization import Uniform, Constant
x = tensor.tensor4('images')
y = tensor.lmatrix('targets')
# Convolutional layers
filter_sizes = [(5, 5)] * 3 + [(4, 4)] * 3
num_filters = [32, 32, 64, 64, 128, 256]
pooling_sizes = [(2, 2)] * 6
activation = Rectifier().apply
conv_layers = [
ConvolutionalLayer(activation, filter_size, num_filters_, pooling_size)
for filter_size, num_filters_, pooling_size in zip(
filter_sizes, num_filters, pooling_sizes)
]
convnet = ConvolutionalSequence(conv_layers,
num_channels=3,
image_size=(260, 260),
weights_init=Uniform(0, 0.2),
biases_init=Constant(0.))
convnet.initialize()
# Fully connected layers
features = Flattener().apply(convnet.apply(x))
mlp = MLP(activations=[Rectifier(), None],
dims=[256, 256, 2],
def run_experiment():
np.random.seed(42)
#X = tensor.matrix('features')
X = tensor.tensor4('features')
y = tensor.matrix('targets')
nbr_channels = 3
image_shape = (30, 30)
conv_layers = [
ConvolutionalLayer(filter_size=(4, 4),
num_filters=10,
activation=Rectifier().apply,
border_mode='full',
pooling_size=(1, 1),
weights_init=Uniform(width=0.1),
biases_init=Constant(0.0),
name='conv0'),
ConvolutionalLayer(filter_size=(3, 3),
num_filters=14,
activation=Rectifier().apply,
border_mode='full',
pooling_size=(1, 1),
weights_init=Uniform(width=0.1),
biases_init=Constant(0.0),
name='conv1')
]
conv_sequence = ConvolutionalSequence(conv_layers,
num_channels=nbr_channels,
image_size=image_shape)
#conv_sequence.push_allocation_config()
conv_sequence.initialize()
conv_output_dim = np.prod(conv_sequence.get_dim('output'))
#conv_output_dim = 25*25
flattener = Flattener()
mlp = MLP(activations=[Rectifier(), Rectifier(),
Softmax()],
dims=[conv_output_dim, 50, 50, 10],
weights_init=IsotropicGaussian(std=0.1),
biases_init=IsotropicGaussian(std=0.01))
mlp.initialize()
conv_output = conv_sequence.apply(X)
y_hat = mlp.apply(flattener.apply(conv_output))
cost = CategoricalCrossEntropy().apply(y, y_hat)
#cost = CategoricalCrossEntropy().apply(y_hat, y)
#cost = BinaryCrossEntropy().apply(y.flatten(), y_hat.flatten())
cg = ComputationGraph([y_hat])
"""
print "--- INPUT ---"
for v in VariableFilter(bricks=mlp.linear_transformations, roles=[INPUT])(cg.variables):
print v.tag.annotations[0].name
print "--- OUTPUT ---"
#print(VariableFilter(bricks=mlp.linear_transformations, roles=[OUTPUT])(cg.variables))
for v in VariableFilter(bricks=mlp.linear_transformations, roles=[OUTPUT])(cg.variables):
print v.tag.annotations[0].name
print "--- WEIGHT ---"
#print(VariableFilter(bricks=mlp.linear_transformations, roles=[WEIGHT])(cg.variables))
for v in VariableFilter(bricks=mlp.linear_transformations, roles=[WEIGHT])(cg.variables):
print v.tag.annotations[0].name
print "--- BIAS ---"
#print(VariableFilter(bricks=mlp.linear_transformations, roles=[BIAS])(cg.variables))
for v in VariableFilter(bricks=mlp.linear_transformations, roles=[BIAS])(cg.variables):
print v.tag.annotations[0].name
"""
# check out .tag on the variables to see which layer they belong to
print "----------------------------"
D_by_layer = get_linear_transformation_roles(mlp, cg)
# returns a vector with one entry for each in the mini-batch
individual_sum_square_norm_gradients_method_00 = get_sum_square_norm_gradients_linear_transformations(
D_by_layer, cost)
#import pprint
#pp = pprint.PrettyPrinter(indent=4)
#pp.pprint(get_conv_layers_transformation_roles(ComputationGraph(conv_output)).items())
D_by_layer = get_conv_layers_transformation_roles(
ComputationGraph(conv_output))
individual_sum_square_norm_gradients_method_00 += get_sum_square_norm_gradients_conv_transformations(
D_by_layer, cost)
print "There are %d entries in cg.parameters." % len(cg.parameters)
L_grads_method_01 = [tensor.grad(cost, p) for p in cg.parameters]
L_grads_method_02 = [
tensor.grad(cost, v)
for v in VariableFilter(roles=[WEIGHT, BIAS])(cg.variables)
]
# works on the sum of the gradients in a mini-batch
sum_square_norm_gradients_method_01 = sum(
[tensor.sqr(g).sum() for g in L_grads_method_01])
sum_square_norm_gradients_method_02 = sum(
[tensor.sqr(g).sum() for g in L_grads_method_02])
N = 8
Xtrain = np.random.randn(N, nbr_channels, image_shape[0],
image_shape[1]).astype(np.float32)
# Option 1.
ytrain = np.zeros((N, 10), dtype=np.float32)
for n in range(N):
label = np.random.randint(low=0, high=10)
ytrain[n, label] = 1.0
# Option 2, just to debug situations with NaN.
#ytrain = np.random.rand(N, 10).astype(np.float32)
#for n in range(N):
# ytrain[n,:] = ytrain[n,:] / ytrain[n,:].sum()
f = theano.function([X, y], [
cost, individual_sum_square_norm_gradients_method_00,
sum_square_norm_gradients_method_01,
sum_square_norm_gradients_method_02
])
[c, v0, gs1, gs2] = f(Xtrain, ytrain)
#print "[c, v0, gs1, gs2]"
L_c, L_v0, L_gs1, L_gs2 = ([], [], [], [])
for n in range(N):
[nc, nv0, ngs1, ngs2] = f(
Xtrain[n, :].reshape(
(1, Xtrain.shape[1], Xtrain.shape[2], Xtrain.shape[3])),
ytrain[n, :].reshape((1, 10)))
L_c.append(nc)
L_v0.append(nv0)
L_gs1.append(ngs1)
L_gs2.append(ngs2)
print "Cost for whole mini-batch in single shot : %f." % c
print "Cost for whole mini-batch accumulated : %f." % sum(L_c)
print ""
print "Square-norm of all gradients for each data point in single shot :"
print v0.reshape((1, -1))
print "Square-norm of all gradients for each data point iteratively :"
print np.array(L_gs1).reshape((1, -1))
print "Square-norm of all gradients for each data point iteratively :"
print np.array(L_gs2).reshape((1, -1))
print ""
print "Difference max abs : %f." % np.max(np.abs(v0 - np.array(L_gs1)))
print "Difference max abs : %f." % np.max(np.abs(v0 - np.array(L_gs2)))
print ""
print "Ratios : "
print np.array(L_gs1).reshape((1, -1)) / v0.reshape((1, -1))
