Mercurial > ift6266
comparison deep/convolutional_dae/stacked_convolutional_dae.py @ 167:1f5937e9e530
More moves - transformations into data_generation, added "deep" folder
author | Dumitru Erhan <dumitru.erhan@gmail.com> |
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date | Fri, 26 Feb 2010 14:15:38 -0500 |
parents | scripts/stacked_dae/stacked_convolutional_dae.py@128507ac4edf |
children | 3f2cc90ad51c |
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166:17ae5a1a4dd1 | 167:1f5937e9e530 |
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1 import numpy | |
2 import theano | |
3 import time | |
4 import theano.tensor as T | |
5 from theano.tensor.shared_randomstreams import RandomStreams | |
6 import theano.sandbox.softsign | |
7 | |
8 from theano.tensor.signal import downsample | |
9 from theano.tensor.nnet import conv | |
10 import gzip | |
11 import cPickle | |
12 | |
13 | |
14 class LogisticRegression(object): | |
15 | |
16 def __init__(self, input, n_in, n_out): | |
17 | |
18 self.W = theano.shared( value=numpy.zeros((n_in,n_out), | |
19 dtype = theano.config.floatX) ) | |
20 | |
21 self.b = theano.shared( value=numpy.zeros((n_out,), | |
22 dtype = theano.config.floatX) ) | |
23 | |
24 self.p_y_given_x = T.nnet.softmax(T.dot(input, self.W)+self.b) | |
25 | |
26 | |
27 self.y_pred=T.argmax(self.p_y_given_x, axis=1) | |
28 | |
29 self.params = [self.W, self.b] | |
30 | |
31 def negative_log_likelihood(self, y): | |
32 return -T.mean(T.log(self.p_y_given_x)[T.arange(y.shape[0]),y]) | |
33 | |
34 def MSE(self, y): | |
35 return -T.mean(abs((self.p_y_given_x)[T.arange(y.shape[0]),y]-y)**2) | |
36 | |
37 def errors(self, y): | |
38 if y.ndim != self.y_pred.ndim: | |
39 raise TypeError('y should have the same shape as self.y_pred', | |
40 ('y', target.type, 'y_pred', self.y_pred.type)) | |
41 | |
42 | |
43 if y.dtype.startswith('int'): | |
44 return T.mean(T.neq(self.y_pred, y)) | |
45 else: | |
46 raise NotImplementedError() | |
47 | |
48 | |
49 class SigmoidalLayer(object): | |
50 def __init__(self, rng, input, n_in, n_out): | |
51 | |
52 self.input = input | |
53 | |
54 W_values = numpy.asarray( rng.uniform( \ | |
55 low = -numpy.sqrt(6./(n_in+n_out)), \ | |
56 high = numpy.sqrt(6./(n_in+n_out)), \ | |
57 size = (n_in, n_out)), dtype = theano.config.floatX) | |
58 self.W = theano.shared(value = W_values) | |
59 | |
60 b_values = numpy.zeros((n_out,), dtype= theano.config.floatX) | |
61 self.b = theano.shared(value= b_values) | |
62 | |
63 self.output = T.tanh(T.dot(input, self.W) + self.b) | |
64 self.params = [self.W, self.b] | |
65 | |
66 class dA_conv(object): | |
67 | |
68 def __init__(self, corruption_level = 0.1, input = None, shared_W = None,\ | |
69 shared_b = None, filter_shape = None, image_shape = None, poolsize = (2,2)): | |
70 | |
71 theano_rng = RandomStreams() | |
72 | |
73 fan_in = numpy.prod(filter_shape[1:]) | |
74 fan_out = filter_shape[0] * numpy.prod(filter_shape[2:]) | |
75 | |
76 center = theano.shared(value = 1, name="center") | |
77 scale = theano.shared(value = 2, name="scale") | |
78 | |
79 if shared_W != None and shared_b != None : | |
80 self.W = shared_W | |
81 self.b = shared_b | |
82 else: | |
83 initial_W = numpy.asarray( numpy.random.uniform( \ | |
84 low = -numpy.sqrt(6./(fan_in+fan_out)), \ | |
85 high = numpy.sqrt(6./(fan_in+fan_out)), \ | |
86 size = filter_shape), dtype = theano.config.floatX) | |
87 initial_b = numpy.zeros((filter_shape[0],), dtype= theano.config.floatX) | |
88 | |
89 | |
90 self.W = theano.shared(value = initial_W, name = "W") | |
91 self.b = theano.shared(value = initial_b, name = "b") | |
92 | |
93 | |
94 initial_b_prime= numpy.zeros((filter_shape[1],)) | |
95 | |
96 self.W_prime=T.dtensor4('W_prime') | |
97 | |
98 self.b_prime = theano.shared(value = initial_b_prime, name = "b_prime") | |
99 | |
100 self.x = input | |
101 | |
102 self.tilde_x = theano_rng.binomial( self.x.shape, 1, 1 - corruption_level) * self.x | |
103 | |
104 conv1_out = conv.conv2d(self.tilde_x, self.W, \ | |
105 filter_shape=filter_shape, \ | |
106 image_shape=image_shape, border_mode='valid') | |
107 | |
108 | |
109 self.y = T.tanh(conv1_out + self.b.dimshuffle('x', 0, 'x', 'x')) | |
110 | |
111 | |
112 da_filter_shape = [ filter_shape[1], filter_shape[0], filter_shape[2],\ | |
113 filter_shape[3] ] | |
114 da_image_shape = [ image_shape[0],filter_shape[0],image_shape[2]-filter_shape[2]+1, \ | |
115 image_shape[3]-filter_shape[3]+1 ] | |
116 initial_W_prime = numpy.asarray( numpy.random.uniform( \ | |
117 low = -numpy.sqrt(6./(fan_in+fan_out)), \ | |
118 high = numpy.sqrt(6./(fan_in+fan_out)), \ | |
119 size = da_filter_shape), dtype = theano.config.floatX) | |
120 self.W_prime = theano.shared(value = initial_W_prime, name = "W_prime") | |
121 | |
122 #import pdb;pdb.set_trace() | |
123 | |
124 conv2_out = conv.conv2d(self.y, self.W_prime, \ | |
125 filter_shape = da_filter_shape, image_shape = da_image_shape ,\ | |
126 border_mode='full') | |
127 | |
128 self.z = (T.tanh(conv2_out + self.b_prime.dimshuffle('x', 0, 'x', 'x'))+center) / scale | |
129 | |
130 scaled_x = (self.x + center) / scale | |
131 | |
132 self.L = - T.sum( scaled_x*T.log(self.z) + (1-scaled_x)*T.log(1-self.z), axis=1 ) | |
133 | |
134 self.cost = T.mean(self.L) | |
135 | |
136 self.params = [ self.W, self.b, self.b_prime ] | |
137 | |
138 | |
139 | |
140 class LeNetConvPoolLayer(object): | |
141 def __init__(self, rng, input, filter_shape, image_shape, poolsize=(2,2)): | |
142 assert image_shape[1]==filter_shape[1] | |
143 self.input = input | |
144 | |
145 W_values = numpy.zeros(filter_shape, dtype=theano.config.floatX) | |
146 self.W = theano.shared(value = W_values) | |
147 | |
148 b_values = numpy.zeros((filter_shape[0],), dtype= theano.config.floatX) | |
149 self.b = theano.shared(value= b_values) | |
150 | |
151 conv_out = conv.conv2d(input, self.W, | |
152 filter_shape=filter_shape, image_shape=image_shape) | |
153 | |
154 | |
155 fan_in = numpy.prod(filter_shape[1:]) | |
156 fan_out = filter_shape[0] * numpy.prod(filter_shape[2:]) / numpy.prod(poolsize) | |
157 | |
158 W_bound = numpy.sqrt(6./(fan_in + fan_out)) | |
159 self.W.value = numpy.asarray( | |
160 rng.uniform(low=-W_bound, high=W_bound, size=filter_shape), | |
161 dtype = theano.config.floatX) | |
162 | |
163 | |
164 pooled_out = downsample.max_pool2D(conv_out, poolsize, ignore_border=True) | |
165 | |
166 self.output = T.tanh(pooled_out + self.b.dimshuffle('x', 0, 'x', 'x')) | |
167 self.params = [self.W, self.b] | |
168 | |
169 | |
170 class SdA(): | |
171 def __init__(self, input, n_ins_conv, n_ins_mlp, train_set_x, train_set_y, batch_size, \ | |
172 conv_hidden_layers_sizes, mlp_hidden_layers_sizes, corruption_levels, \ | |
173 rng, n_out, pretrain_lr, finetune_lr): | |
174 | |
175 self.layers = [] | |
176 self.pretrain_functions = [] | |
177 self.params = [] | |
178 self.conv_n_layers = len(conv_hidden_layers_sizes) | |
179 self.mlp_n_layers = len(mlp_hidden_layers_sizes) | |
180 | |
181 index = T.lscalar() # index to a [mini]batch | |
182 self.x = T.dmatrix('x') # the data is presented as rasterized images | |
183 self.y = T.ivector('y') # the labels are presented as 1D vector of | |
184 | |
185 | |
186 | |
187 for i in xrange( self.conv_n_layers ): | |
188 | |
189 filter_shape=conv_hidden_layers_sizes[i][0] | |
190 image_shape=conv_hidden_layers_sizes[i][1] | |
191 max_poolsize=conv_hidden_layers_sizes[i][2] | |
192 | |
193 if i == 0 : | |
194 layer_input=self.x.reshape((batch_size,1,28,28)) | |
195 else: | |
196 layer_input=self.layers[-1].output | |
197 | |
198 layer = LeNetConvPoolLayer(rng, input=layer_input, \ | |
199 image_shape=image_shape, \ | |
200 filter_shape=filter_shape,poolsize=max_poolsize) | |
201 print 'Convolutional layer '+str(i+1)+' created' | |
202 | |
203 self.layers += [layer] | |
204 self.params += layer.params | |
205 | |
206 da_layer = dA_conv(corruption_level = corruption_levels[0],\ | |
207 input = layer_input, \ | |
208 shared_W = layer.W, shared_b = layer.b,\ | |
209 filter_shape = filter_shape , image_shape = image_shape ) | |
210 | |
211 | |
212 gparams = T.grad(da_layer.cost, da_layer.params) | |
213 | |
214 updates = {} | |
215 for param, gparam in zip(da_layer.params, gparams): | |
216 updates[param] = param - gparam * pretrain_lr | |
217 | |
218 | |
219 update_fn = theano.function([index], da_layer.cost, \ | |
220 updates = updates, | |
221 givens = { | |
222 self.x : train_set_x[index*batch_size:(index+1)*batch_size]} ) | |
223 | |
224 self.pretrain_functions += [update_fn] | |
225 | |
226 for i in xrange( self.mlp_n_layers ): | |
227 if i == 0 : | |
228 input_size = n_ins_mlp | |
229 else: | |
230 input_size = mlp_hidden_layers_sizes[i-1] | |
231 | |
232 if i == 0 : | |
233 if len( self.layers ) == 0 : | |
234 layer_input=self.x | |
235 else : | |
236 layer_input = self.layers[-1].output.flatten(2) | |
237 else: | |
238 layer_input = self.layers[-1].output | |
239 | |
240 layer = SigmoidalLayer(rng, layer_input, input_size, | |
241 mlp_hidden_layers_sizes[i] ) | |
242 | |
243 self.layers += [layer] | |
244 self.params += layer.params | |
245 | |
246 | |
247 print 'MLP layer '+str(i+1)+' created' | |
248 | |
249 self.logLayer = LogisticRegression(input=self.layers[-1].output, \ | |
250 n_in=mlp_hidden_layers_sizes[-1], n_out=n_out) | |
251 self.params += self.logLayer.params | |
252 | |
253 cost = self.logLayer.negative_log_likelihood(self.y) | |
254 | |
255 gparams = T.grad(cost, self.params) | |
256 updates = {} | |
257 | |
258 for param,gparam in zip(self.params, gparams): | |
259 updates[param] = param - gparam*finetune_lr | |
260 | |
261 self.finetune = theano.function([index], cost, | |
262 updates = updates, | |
263 givens = { | |
264 self.x : train_set_x[index*batch_size:(index+1)*batch_size], | |
265 self.y : train_set_y[index*batch_size:(index+1)*batch_size]} ) | |
266 | |
267 | |
268 self.errors = self.logLayer.errors(self.y) | |
269 | |
270 | |
271 | |
272 def sgd_optimization_mnist( learning_rate=0.1, pretraining_epochs = 2, \ | |
273 pretrain_lr = 0.01, training_epochs = 1000, \ | |
274 dataset='mnist.pkl.gz'): | |
275 | |
276 f = gzip.open(dataset,'rb') | |
277 train_set, valid_set, test_set = cPickle.load(f) | |
278 f.close() | |
279 | |
280 | |
281 def shared_dataset(data_xy): | |
282 data_x, data_y = data_xy | |
283 shared_x = theano.shared(numpy.asarray(data_x, dtype=theano.config.floatX)) | |
284 shared_y = theano.shared(numpy.asarray(data_y, dtype=theano.config.floatX)) | |
285 return shared_x, T.cast(shared_y, 'int32') | |
286 | |
287 | |
288 test_set_x, test_set_y = shared_dataset(test_set) | |
289 valid_set_x, valid_set_y = shared_dataset(valid_set) | |
290 train_set_x, train_set_y = shared_dataset(train_set) | |
291 | |
292 batch_size = 500 # size of the minibatch | |
293 | |
294 | |
295 n_train_batches = train_set_x.value.shape[0] / batch_size | |
296 n_valid_batches = valid_set_x.value.shape[0] / batch_size | |
297 n_test_batches = test_set_x.value.shape[0] / batch_size | |
298 | |
299 # allocate symbolic variables for the data | |
300 index = T.lscalar() # index to a [mini]batch | |
301 x = T.matrix('x') # the data is presented as rasterized images | |
302 y = T.ivector('y') # the labels are presented as 1d vector of | |
303 # [int] labels | |
304 layer0_input = x.reshape((batch_size,1,28,28)) | |
305 | |
306 | |
307 # Setup the convolutional layers with their DAs(add as many as you want) | |
308 corruption_levels = [ 0.2, 0.2, 0.2] | |
309 rng = numpy.random.RandomState(1234) | |
310 ker1=2 | |
311 ker2=2 | |
312 conv_layers=[] | |
313 conv_layers.append([[ker1,1,5,5], [batch_size,1,28,28], [2,2] ]) | |
314 conv_layers.append([[ker2,ker1,5,5], [batch_size,ker1,12,12], [2,2] ]) | |
315 | |
316 # Setup the MLP layers of the network | |
317 mlp_layers=[500] | |
318 | |
319 network = SdA(input = layer0_input, n_ins_conv = 28*28, n_ins_mlp = ker2*4*4, \ | |
320 train_set_x = train_set_x, train_set_y = train_set_y, batch_size = batch_size, | |
321 conv_hidden_layers_sizes = conv_layers, \ | |
322 mlp_hidden_layers_sizes = mlp_layers, \ | |
323 corruption_levels = corruption_levels , n_out = 10, \ | |
324 rng = rng , pretrain_lr = pretrain_lr , finetune_lr = learning_rate ) | |
325 | |
326 test_model = theano.function([index], network.errors, | |
327 givens = { | |
328 network.x: test_set_x[index*batch_size:(index+1)*batch_size], | |
329 network.y: test_set_y[index*batch_size:(index+1)*batch_size]}) | |
330 | |
331 validate_model = theano.function([index], network.errors, | |
332 givens = { | |
333 network.x: valid_set_x[index*batch_size:(index+1)*batch_size], | |
334 network.y: valid_set_y[index*batch_size:(index+1)*batch_size]}) | |
335 | |
336 | |
337 | |
338 start_time = time.clock() | |
339 for i in xrange(len(network.layers)-len(mlp_layers)): | |
340 for epoch in xrange(pretraining_epochs): | |
341 for batch_index in xrange(n_train_batches): | |
342 c = network.pretrain_functions[i](batch_index) | |
343 print 'pre-training convolution layer %i, epoch %d, cost '%(i,epoch),c | |
344 | |
345 patience = 10000 # look as this many examples regardless | |
346 patience_increase = 2. # WAIT THIS MUCH LONGER WHEN A NEW BEST IS | |
347 # FOUND | |
348 improvement_threshold = 0.995 # a relative improvement of this much is | |
349 | |
350 validation_frequency = min(n_train_batches, patience/2) | |
351 | |
352 | |
353 best_params = None | |
354 best_validation_loss = float('inf') | |
355 test_score = 0. | |
356 start_time = time.clock() | |
357 | |
358 done_looping = False | |
359 epoch = 0 | |
360 | |
361 while (epoch < training_epochs) and (not done_looping): | |
362 epoch = epoch + 1 | |
363 for minibatch_index in xrange(n_train_batches): | |
364 | |
365 cost_ij = network.finetune(minibatch_index) | |
366 iter = epoch * n_train_batches + minibatch_index | |
367 | |
368 if (iter+1) % validation_frequency == 0: | |
369 | |
370 validation_losses = [validate_model(i) for i in xrange(n_valid_batches)] | |
371 this_validation_loss = numpy.mean(validation_losses) | |
372 print('epoch %i, minibatch %i/%i, validation error %f %%' % \ | |
373 (epoch, minibatch_index+1, n_train_batches, \ | |
374 this_validation_loss*100.)) | |
375 | |
376 | |
377 # if we got the best validation score until now | |
378 if this_validation_loss < best_validation_loss: | |
379 | |
380 #improve patience if loss improvement is good enough | |
381 if this_validation_loss < best_validation_loss * \ | |
382 improvement_threshold : | |
383 patience = max(patience, iter * patience_increase) | |
384 | |
385 # save best validation score and iteration number | |
386 best_validation_loss = this_validation_loss | |
387 best_iter = iter | |
388 | |
389 # test it on the test set | |
390 test_losses = [test_model(i) for i in xrange(n_test_batches)] | |
391 test_score = numpy.mean(test_losses) | |
392 print((' epoch %i, minibatch %i/%i, test error of best ' | |
393 'model %f %%') % | |
394 (epoch, minibatch_index+1, n_train_batches, | |
395 test_score*100.)) | |
396 | |
397 | |
398 if patience <= iter : | |
399 done_looping = True | |
400 break | |
401 | |
402 end_time = time.clock() | |
403 print(('Optimization complete with best validation score of %f %%,' | |
404 'with test performance %f %%') % | |
405 (best_validation_loss * 100., test_score*100.)) | |
406 print ('The code ran for %f minutes' % ((end_time-start_time)/60.)) | |
407 | |
408 | |
409 | |
410 | |
411 | |
412 | |
413 if __name__ == '__main__': | |
414 sgd_optimization_mnist() | |
415 |