diff deep/stacked_dae/sgd_optimization.py @ 275:7b4507295eba

merge
author Xavier Glorot <glorotxa@iro.umontreal.ca>
date Mon, 22 Mar 2010 10:20:10 -0400
parents acb942530923 c8fe09a65039
children 8a3af19ae272
line wrap: on
line diff
--- a/deep/stacked_dae/sgd_optimization.py	Mon Mar 22 10:19:45 2010 -0400
+++ b/deep/stacked_dae/sgd_optimization.py	Mon Mar 22 10:20:10 2010 -0400
@@ -15,53 +15,43 @@
 
 from stacked_dae import SdA
 
-def shared_dataset(data_xy):
-    data_x, data_y = data_xy
-    #shared_x = theano.shared(numpy.asarray(data_x, dtype=theano.config.floatX))
-    #shared_y = theano.shared(numpy.asarray(data_y, dtype=theano.config.floatX))
-    #shared_y = T.cast(shared_y, 'int32')
-    shared_x = theano.shared(data_x)
-    shared_y = theano.shared(data_y)
-    return shared_x, shared_y
+from ift6266.utils.seriestables import *
 
-class DummyMux():
-    def append(self, param1, param2):
-        pass
+default_series = { \
+        'reconstruction_error' : DummySeries(),
+        'training_error' : DummySeries(),
+        'validation_error' : DummySeries(),
+        'test_error' : DummySeries(),
+        'params' : DummySeries()
+        }
+
+def itermax(iter, max):
+    for i,it in enumerate(iter):
+        if i >= max:
+            break
+        yield it
 
 class SdaSgdOptimizer:
-    def __init__(self, dataset, hyperparameters, n_ins, n_outs, input_divider=1.0, series_mux=None):
+    def __init__(self, dataset, hyperparameters, n_ins, n_outs,
+                    examples_per_epoch, series=default_series, max_minibatches=None):
         self.dataset = dataset
         self.hp = hyperparameters
         self.n_ins = n_ins
         self.n_outs = n_outs
-        self.input_divider = input_divider
    
-        if not series_mux:
-            series_mux = DummyMux()
-            print "No series multiplexer set"
-        self.series_mux = series_mux
+        self.max_minibatches = max_minibatches
+        print "SdaSgdOptimizer, max_minibatches =", max_minibatches
+
+        self.ex_per_epoch = examples_per_epoch
+        self.mb_per_epoch = examples_per_epoch / self.hp.minibatch_size
+
+        self.series = series
 
         self.rng = numpy.random.RandomState(1234)
 
-        self.init_datasets()
         self.init_classifier()
 
         sys.stdout.flush()
-     
-    def init_datasets(self):
-        print "init_datasets"
-        sys.stdout.flush()
-
-        train_set, valid_set, test_set = self.dataset
-        self.test_set_x, self.test_set_y = shared_dataset(test_set)
-        self.valid_set_x, self.valid_set_y = shared_dataset(valid_set)
-        self.train_set_x, self.train_set_y = shared_dataset(train_set)
-
-        # compute number of minibatches for training, validation and testing
-        self.n_train_batches = self.train_set_x.value.shape[0] / self.hp.minibatch_size
-        self.n_valid_batches = self.valid_set_x.value.shape[0] / self.hp.minibatch_size
-        # remove last batch in case it's incomplete
-        self.n_test_batches  = (self.test_set_x.value.shape[0]  / self.hp.minibatch_size) - 1
 
     def init_classifier(self):
         print "Constructing classifier"
@@ -74,8 +64,6 @@
 
         # construct the stacked denoising autoencoder class
         self.classifier = SdA( \
-                          train_set_x= self.train_set_x, \
-                          train_set_y = self.train_set_y,\
                           batch_size = self.hp.minibatch_size, \
                           n_ins= self.n_ins, \
                           hidden_layers_sizes = layers_sizes, \
@@ -83,46 +71,44 @@
                           corruption_levels = corruption_levels,\
                           rng = self.rng,\
                           pretrain_lr = self.hp.pretraining_lr, \
-                          finetune_lr = self.hp.finetuning_lr,\
-                          input_divider = self.input_divider )
+                          finetune_lr = self.hp.finetuning_lr)
 
         #theano.printing.pydotprint(self.classifier.pretrain_functions[0], "function.graph")
 
         sys.stdout.flush()
 
     def train(self):
-        self.pretrain()
-        self.finetune()
+        self.pretrain(self.dataset)
+        self.finetune(self.dataset)
 
-    def pretrain(self):
+    def pretrain(self,dataset):
         print "STARTING PRETRAINING, time = ", datetime.datetime.now()
         sys.stdout.flush()
 
-        #time_acc_func = 0.0
-        #time_acc_total = 0.0
-
         start_time = time.clock()  
         ## Pre-train layer-wise 
         for i in xrange(self.classifier.n_layers):
             # go through pretraining epochs 
             for epoch in xrange(self.hp.pretraining_epochs_per_layer):
                 # go through the training set
-                for batch_index in xrange(self.n_train_batches):
-                    #t1 = time.clock()
-                    c = self.classifier.pretrain_functions[i](batch_index)
-                    #t2 = time.clock()
+                batch_index=0
+                for x,y in dataset.train(self.hp.minibatch_size):
+                    c = self.classifier.pretrain_functions[i](x)
+
+                    self.series["reconstruction_error"].append((epoch, batch_index), c)
+                    batch_index+=1
 
-                    #time_acc_func += t2 - t1
+                    #if batch_index % 100 == 0:
+                    #    print "100 batches"
 
-                    #if batch_index % 500 == 0:
-                    #    print "acc / total", time_acc_func / (t2 - start_time), time_acc_func
-
-                    self.series_mux.append("reconstruction_error", c)
+                    # useful when doing tests
+                    if self.max_minibatches and batch_index >= self.max_minibatches:
+                        break
                         
                 print 'Pre-training layer %i, epoch %d, cost '%(i,epoch),c
                 sys.stdout.flush()
 
-                self.series_mux.append("params", self.classifier.all_params)
+                self.series['params'].append((epoch,), self.classifier.all_params)
      
         end_time = time.clock()
 
@@ -131,24 +117,26 @@
 
         sys.stdout.flush()
 
-    def finetune(self):
+    def finetune(self,dataset):
         print "STARTING FINETUNING, time = ", datetime.datetime.now()
 
-        index   = T.lscalar()    # index to a [mini]batch 
         minibatch_size = self.hp.minibatch_size
 
         # create a function to compute the mistakes that are made by the model
         # on the validation set, or testing set
-        shared_divider = theano.shared(numpy.asarray(self.input_divider, dtype=theano.config.floatX))
-        test_model = theano.function([index], self.classifier.errors,
-                 givens = {
-                   self.classifier.x: self.test_set_x[index*minibatch_size:(index+1)*minibatch_size] / shared_divider,
-                   self.classifier.y: self.test_set_y[index*minibatch_size:(index+1)*minibatch_size]})
+        test_model = \
+            theano.function(
+                [self.classifier.x,self.classifier.y], self.classifier.errors)
+        #         givens = {
+        #           self.classifier.x: ensemble_x,
+        #           self.classifier.y: ensemble_y]})
 
-        validate_model = theano.function([index], self.classifier.errors,
-                givens = {
-                   self.classifier.x: self.valid_set_x[index*minibatch_size:(index+1)*minibatch_size] / shared_divider,
-                   self.classifier.y: self.valid_set_y[index*minibatch_size:(index+1)*minibatch_size]})
+        validate_model = \
+            theano.function(
+                [self.classifier.x,self.classifier.y], self.classifier.errors)
+        #        givens = {
+        #           self.classifier.x: ,
+        #           self.classifier.y: ]})
 
 
         # early-stopping parameters
@@ -157,11 +145,13 @@
                                       # found
         improvement_threshold = 0.995 # a relative improvement of this much is 
                                       # considered significant
-        validation_frequency  = min(self.n_train_batches, patience/2)
+        validation_frequency  = min(self.mb_per_epoch, patience/2)
                                       # go through this many 
                                       # minibatche before checking the network 
                                       # on the validation set; in this case we 
                                       # check every epoch 
+        if self.max_minibatches and validation_frequency > self.max_minibatches:
+            validation_frequency = self.max_minibatches / 2
 
         best_params          = None
         best_validation_loss = float('inf')
@@ -171,22 +161,31 @@
         done_looping = False
         epoch = 0
 
+        total_mb_index = 0
+
         while (epoch < self.hp.max_finetuning_epochs) and (not done_looping):
             epoch = epoch + 1
-            for minibatch_index in xrange(self.n_train_batches):
+            minibatch_index = -1
+            for x,y in dataset.train(minibatch_size):
+                minibatch_index += 1
+                cost_ij = self.classifier.finetune(x,y)
+                total_mb_index += 1
 
-                cost_ij = self.classifier.finetune(minibatch_index)
-                iter    = epoch * self.n_train_batches + minibatch_index
-
-                self.series_mux.append("training_error", cost_ij)
+                self.series["training_error"].append((epoch, minibatch_index), cost_ij)
 
-                if (iter+1) % validation_frequency == 0: 
+                if (total_mb_index+1) % validation_frequency == 0: 
                     
-                    validation_losses = [validate_model(i) for i in xrange(self.n_valid_batches)]
+                    iter = dataset.valid(minibatch_size)
+                    if self.max_minibatches:
+                        iter = itermax(iter, self.max_minibatches)
+                    validation_losses = [validate_model(x,y) for x,y in iter]
                     this_validation_loss = numpy.mean(validation_losses)
-                    self.series_mux.append("validation_error", this_validation_loss)
+
+                    self.series["validation_error"].\
+                        append((epoch, minibatch_index), this_validation_loss*100.)
+
                     print('epoch %i, minibatch %i/%i, validation error %f %%' % \
-                           (epoch, minibatch_index+1, self.n_train_batches, \
+                           (epoch, minibatch_index+1, self.mb_per_epoch, \
                             this_validation_loss*100.))
 
 
@@ -196,26 +195,36 @@
                         #improve patience if loss improvement is good enough
                         if this_validation_loss < best_validation_loss *  \
                                improvement_threshold :
-                            patience = max(patience, iter * patience_increase)
+                            patience = max(patience, total_mb_index * patience_increase)
 
                         # save best validation score and iteration number
                         best_validation_loss = this_validation_loss
-                        best_iter = iter
+                        best_iter = total_mb_index
 
                         # test it on the test set
-                        test_losses = [test_model(i) for i in xrange(self.n_test_batches)]
+                        iter = dataset.test(minibatch_size)
+                        if self.max_minibatches:
+                            iter = itermax(iter, self.max_minibatches)
+                        test_losses = [test_model(x,y) for x,y in iter]
                         test_score = numpy.mean(test_losses)
-                        self.series_mux.append("test_error", test_score)
+
+                        self.series["test_error"].\
+                            append((epoch, minibatch_index), test_score*100.)
+
                         print(('     epoch %i, minibatch %i/%i, test error of best '
                               'model %f %%') % 
-                                     (epoch, minibatch_index+1, self.n_train_batches,
+                                     (epoch, minibatch_index+1, self.mb_per_epoch,
                                       test_score*100.))
 
                     sys.stdout.flush()
 
-            self.series_mux.append("params", self.classifier.all_params)
+                # useful when doing tests
+                if self.max_minibatches and minibatch_index >= self.max_minibatches:
+                    break
 
-            if patience <= iter :
+            self.series['params'].append((epoch,), self.classifier.all_params)
+
+            if patience <= total_mb_index:
                 done_looping = True
                 break