def init_classifier(self):
        print "Constructing classifier"

        n_ins, convlayers = get_conv_shape(
            self.hp.kernels, self.hp.imgshp, self.hp.minibatch_size, self.hp.max_pool_layers
        )

        self.classifier = CSdA(
            n_ins_mlp=n_ins,
            batch_size=self.hp.minibatch_size,
            conv_hidden_layers_sizes=convlayers,
            mlp_hidden_layers_sizes=self.hp.mlp_size,
            corruption_levels=self.hp.corruption_levels,
            rng=self.rng,
            n_out=self.n_outs,
            pretrain_lr=self.hp.pretraining_lr,
            finetune_lr=self.hp.finetuning_lr,
        )

        # theano.printing.pydotprint(self.classifier.pretrain_functions[0], "function.graph")

        sys.stdout.flush()
class CSdASgdOptimizer:
    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.parameters_pre = []

        self.max_minibatches = max_minibatches
        print "CSdASgdOptimizer, 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_classifier()

        sys.stdout.flush()

    def init_classifier(self):
        print "Constructing classifier"

        n_ins, convlayers = get_conv_shape(
            self.hp.kernels, self.hp.imgshp, self.hp.minibatch_size, self.hp.max_pool_layers
        )

        self.classifier = CSdA(
            n_ins_mlp=n_ins,
            batch_size=self.hp.minibatch_size,
            conv_hidden_layers_sizes=convlayers,
            mlp_hidden_layers_sizes=self.hp.mlp_size,
            corruption_levels=self.hp.corruption_levels,
            rng=self.rng,
            n_out=self.n_outs,
            pretrain_lr=self.hp.pretraining_lr,
            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.dataset)
        self.finetune(self.dataset)

    def pretrain(self, dataset):
        print "STARTING PRETRAINING, time = ", datetime.datetime.now()
        sys.stdout.flush()

        un_fichier = int(819200.0 / self.hp.minibatch_size)  # Number of batches in a P07 file

        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
                batch_index = 0
                count = 0
                num_files = 0
                for x, y in dataset.train(self.hp.minibatch_size):
                    if x.shape[0] != self.hp.minibatch_size:
                        continue
                    c = self.classifier.pretrain_functions[i](x)
                    count += 1

                    self.series["reconstruction_error"].append((epoch, batch_index), c)
                    batch_index += 1

                    # if batch_index % 100 == 0:
                    #    print "100 batches"

                    # useful when doing tests
                    if self.max_minibatches and batch_index >= self.max_minibatches:
                        break

                    # When we pass through the data only once (the case with P07)
                    # There is approximately 800*1024=819200 examples per file (1k per example and files are 800M)
                    if self.hp.pretraining_epochs_per_layer == 1 and count % un_fichier == 0:
                        print "Pre-training layer %i, epoch %d, cost " % (i, num_files), c
                        num_files += 1
                        sys.stdout.flush()
                        self.series["params"].append((num_files,), self.classifier.all_params)

                # When NIST is used
                if self.hp.pretraining_epochs_per_layer > 1:
                    print "Pre-training layer %i, epoch %d, cost " % (i, epoch), c
                    sys.stdout.flush()

                    self.series["params"].append((epoch,), self.classifier.all_params)
        end_time = time.clock()

        print ("Pretraining took %f minutes" % ((end_time - start_time) / 60.0))
        self.hp.update({"pretraining_time": end_time - start_time})

        sys.stdout.flush()

        # To be able to load them later for tests on finetune
        self.parameters_pre = [copy(x.value) for x in self.classifier.params]
        f = open("params_pretrain.txt", "w")
        pickle.dump(self.parameters_pre, f)
        f.close()

    def finetune(self, dataset, dataset_test, num_finetune, ind_test, special=0, decrease=0):

        if special != 0 and special != 1:
            sys.exit("Bad value for variable special. Must be in {0,1}")
        print "STARTING FINETUNING, time = ", datetime.datetime.now()

        minibatch_size = self.hp.minibatch_size
        if ind_test == 0 or ind_test == 20:
            nom_test = "NIST"
            nom_train = "P07"
        else:
            nom_test = "P07"
            nom_train = "NIST"

        # create a function to compute the mistakes that are made by the model
        # on the validation set, or testing set
        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([self.classifier.x, self.classifier.y], self.classifier.errors)
        #        givens = {
        #           self.classifier.x: ,
        #           self.classifier.y: ]})
        # early-stopping parameters
        patience = 10000  # look as this many examples regardless
        patience_increase = 2.0  # wait this much longer when a new best is
        # found
        improvement_threshold = 0.995  # a relative improvement of this much is
        # considered significant
        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")
        test_score = 0.0
        start_time = time.clock()

        done_looping = False
        epoch = 0

        total_mb_index = 0
        minibatch_index = 0
        parameters_finetune = []
        learning_rate = self.hp.finetuning_lr

        while (epoch < num_finetune) and (not done_looping):
            epoch = epoch + 1

            for x, y in dataset.train(minibatch_size, bufsize=buffersize):

                minibatch_index += 1

                if x.shape[0] != self.hp.minibatch_size:
                    print "bim"
                    continue

                cost_ij = self.classifier.finetune(x, y)  # ,learning_rate)
                total_mb_index += 1

                self.series["training_error"].append((epoch, minibatch_index), cost_ij)

                if (total_mb_index + 1) % validation_frequency == 0:
                    # minibatch_index += 1
                    # The validation set is always NIST (we want the model to be good on NIST)

                    iter = dataset_test.valid(minibatch_size, bufsize=buffersize)

                    if self.max_minibatches:
                        iter = itermax(iter, self.max_minibatches)

                    validation_losses = []

                    for x, y in iter:
                        if x.shape[0] != self.hp.minibatch_size:
                            print "bim"
                            continue
                        validation_losses.append(validate_model(x, y))

                    this_validation_loss = numpy.mean(validation_losses)

                    self.series["validation_error"].append((epoch, minibatch_index), this_validation_loss * 100.0)

                    print (
                        "epoch %i, minibatch %i, validation error on NIST : %f %%"
                        % (epoch, minibatch_index + 1, this_validation_loss * 100.0)
                    )

                    # if we got the best validation score until now
                    if this_validation_loss < best_validation_loss:

                        # improve patience if loss improvement is good enough
                        if this_validation_loss < best_validation_loss * improvement_threshold:
                            patience = max(patience, total_mb_index * patience_increase)

                        # save best validation score, iteration number and parameters
                        best_validation_loss = this_validation_loss
                        best_iter = total_mb_index
                        parameters_finetune = [copy(x.value) for x in self.classifier.params]

                        # test it on the test set
                        iter = dataset.test(minibatch_size, bufsize=buffersize)
                        if self.max_minibatches:
                            iter = itermax(iter, self.max_minibatches)
                        test_losses = []
                        test_losses2 = []
                        for x, y in iter:
                            if x.shape[0] != self.hp.minibatch_size:
                                print "bim"
                                continue
                            test_losses.append(test_model(x, y))

                        test_score = numpy.mean(test_losses)

                        # test it on the second test set
                        iter2 = dataset_test.test(minibatch_size, bufsize=buffersize)
                        if self.max_minibatches:
                            iter2 = itermax(iter2, self.max_minibatches)
                        for x, y in iter2:
                            if x.shape[0] != self.hp.minibatch_size:
                                continue
                            test_losses2.append(test_model(x, y))

                        test_score2 = numpy.mean(test_losses2)

                        self.series["test_error"].append((epoch, minibatch_index), test_score * 100.0)

                        print (
                            (
                                "     epoch %i, minibatch %i, test error on dataset %s  (train data) of best "
                                "model %f %%"
                            )
                            % (epoch, minibatch_index + 1, nom_train, test_score * 100.0)
                        )

                        print (
                            ("     epoch %i, minibatch %i, test error on dataset %s of best " "model %f %%")
                            % (epoch, minibatch_index + 1, nom_test, test_score2 * 100.0)
                        )

                    if patience <= total_mb_index:
                        done_looping = True
                        break  # to exit the FOR loop

                    sys.stdout.flush()

                # useful when doing tests
                if self.max_minibatches and minibatch_index >= self.max_minibatches:
                    break

            if decrease == 1:
                learning_rate /= 2  # divide the learning rate by 2 for each new epoch

            self.series["params"].append((epoch,), self.classifier.all_params)

            if done_looping == True:  # To exit completly the fine-tuning
                break  # to exit the WHILE loop

        end_time = time.clock()
        self.hp.update(
            {
                "finetuning_time": end_time - start_time,
                "best_validation_error": best_validation_loss,
                "test_score": test_score,
                "num_finetuning_epochs": epoch,
            }
        )

        print (
            (
                "\nOptimization complete with best validation score of %f %%,"
                "with test performance %f %% on dataset %s "
            )
            % (best_validation_loss * 100.0, test_score * 100.0, nom_train)
        )
        print (("The test score on the %s dataset is %f") % (nom_test, test_score2 * 100.0))

        print ("The finetuning ran for %f minutes" % ((end_time - start_time) / 60.0))

        sys.stdout.flush()

        # Save a copy of the parameters in a file to be able to get them in the future

        if special == 1:  # To keep a track of the value of the parameters
            f = open("params_finetune_stanford.txt", "w")
            pickle.dump(parameters_finetune, f)
            f.close()

        elif ind_test == 0 | ind_test == 20:  # To keep a track of the value of the parameters
            f = open("params_finetune_P07.txt", "w")
            pickle.dump(parameters_finetune, f)
            f.close()

        elif ind_test == 1:  # For the run with 2 finetunes. It will be faster.
            f = open("params_finetune_NIST.txt", "w")
            pickle.dump(parameters_finetune, f)
            f.close()

        elif ind_test == 21:  # To keep a track of the value of the parameters
            f = open("params_finetune_P07_then_NIST.txt", "w")
            pickle.dump(parameters_finetune, f)
            f.close()

    # Set parameters like they where right after pre-train or finetune
    def reload_parameters(self, which):

        # self.parameters_pre=pickle.load('params_pretrain.txt')
        f = open(which)
        self.parameters_pre = pickle.load(f)
        f.close()
        for idx, x in enumerate(self.parameters_pre):
            if x.dtype == "float64":
                self.classifier.params[idx].value = theano._asarray(copy(x), dtype=theano.config.floatX)
            else:
                self.classifier.params[idx].value = copy(x)

    def training_error(self, dataset):
        # create a function to compute the mistakes that are made by the model
        # on the validation set, or testing set
        test_model = theano.function([self.classifier.x, self.classifier.y], self.classifier.errors)

        iter2 = dataset.train(self.hp.minibatch_size, bufsize=buffersize)
        train_losses2 = [test_model(x, y) for x, y in iter2]
        train_score2 = numpy.mean(train_losses2)
        print "Training error is: " + str(train_score2)