def create_member(self, data_files): #Gets the training indexes if self.member_number > 0: train_indexes = \ self.resampler.make_new_train(self.params.resample_size) else: train_indexes = [None, None] #Packs the needed data dataset = [train_indexes, data_files] #Trains the model m = mlp.sequential_model(dataset, self.params, member_number=self.member_number) #Gets the errors for the train set and updates the weights print('Getting the train errors and updating the weights') errors = common.errors(m, data_files[0], self.params.batch_size) e = np.sum((errors * self.D)) if e > 0: n_classes = data_files[0]['y'].shape[1] alpha = .5 * (math.log((1 - e) / e) + math.log(n_classes - 1)) if alpha <= 0.0: #By setting to 0 (instead of crashing), we should avoid # cicleci problems print("\nWARNING - NEGATIVE ALPHA (setting to 0.0)\n") alpha = 0.0 w = np.where(errors == 1, self.D * math.exp(alpha), self.D * math.exp(-alpha)) self.D = w / w.sum() else: alpha = 1.0 / (self.member_number + 1) self.resampler.update_weights(self.D) self.alphas.append(alpha) self.member_number += 1 return (m.to_yaml(), m.get_weights())
def create_member(self): train_set, sample_weights = self.resampler.make_new_train( self.params.resample_size) if self.member_number > 0: resampled = [ train_set, self.resampler.get_valid(), self.resampler.get_test() ] else: sample_weights = None resampled = [ self.resampler.get_train(), self.resampler.get_valid(), self.resampler.get_test() ] m = mlp.sequential_model(resampled, self.params, member_number=self.member_number, sample_weight=sample_weights) orig_train = self.resampler.get_train() errors = common.errors(m, orig_train[0], orig_train[1]) e = np.sum((errors * self.D)) if e > 0: alpha = .5 * math.log((1 - e) / e) w = np.where(errors == 1, self.D * math.exp(alpha), self.D * math.exp(-alpha)) self.D = w / w.sum() else: alpha = 1.0 / (self.member_number + 1) self.resampler.update_weights(self.D) self.alphas.append(alpha) self.member_number += 1 return (m.to_yaml(), m.get_weights())
def create_member(self): self.set_defaults() if self.member_number > 0: if self.resample: train_set, sample_weights = self.resampler.make_new_train( self.params.resample_size) resampled = [ train_set, self.resampler.get_valid(), self.resampler.get_test() ] else: sample_weights = self.D resampled = [ self.resampler.get_train(), self.resampler.get_valid(), self.resampler.get_test() ] else: sample_weights = None resampled = [ self.resampler.get_train(), self.resampler.get_valid(), self.resampler.get_test() ] if self.member_number > 0: self.params.n_epochs = self.n_epochs_after_first if not self.use_sample_weights: sample_weights = None m = mlp.sequential_model( resampled, self.params, member_number=self.member_number, model_weights=self.weights, #the copy is because there is a bug in Keras that deletes names model_config=copy.deepcopy(self.model_config), frozen_layers=self.frozen_layers, sample_weight=sample_weights) self.weights = [l.get_weights() for l in m.layers] injection_index = self.incremental_index + self.member_number if self.incremental_layers is not None: if injection_index == -1: injection_index = len(self.model_config) new_layers = [] for i, l in enumerate(self.incremental_layers): new_layers.append(copy.deepcopy(l)) #make residual block new_block = self._residual_block(injection_index, new_layers, m, self.member_number) new_model_config = self.model_config[:injection_index] + [ new_block ] + self.model_config[injection_index:] if self.freeze_old_layers: self.frozen_layers = list(range(0, injection_index)) self.model_config = copy.deepcopy(new_model_config) self.weights = self.weights[:injection_index] orig_train = self.resampler.get_train() K = orig_train[1].shape[1] self.n_classes = K errors = common.errors(m, orig_train[0], orig_train[1]) error_rate = np.mean(errors) if error_rate >= 1. - (1. / K): return (None, None, False) if self.real: #Real BRN print(("-" * 40)) print(("error rate: {}".format(error_rate))) if error_rate > 0: continue_boosting = True y_coding = np.where(orig_train[1] == 0., -1. / (K - 1), 1.) proba = m.predict(orig_train[0]) proba[proba < np.finfo(proba.dtype).eps] = np.finfo( proba.dtype).eps print((proba[:10])) print((self.D[:10])) factor = np.exp( -1. * (((K - 1.) / K) * inner1d(y_coding, np.log(proba)))) print((factor[:10])) w = self.D * factor print((w[:10])) self.D = w / w.sum() self.resampler.update_weights(self.D) else: continue_boosting = not self.early_stopping self.member_number += 1 return (m.to_yaml(), m.get_weights(), continue_boosting) else: if error_rate > 0: continue_boosting = True #e = sum((errors * self.D)) / sum(self.D) e = np.average(errors, weights=self.D) alpha = math.log((1 - e) / e) + math.log(K - 1) factor = np.clip( np.where(errors == 1, math.exp(alpha), math.exp(-alpha)), 1e-3, 1e3) w = self.D * factor self.D = w / w.sum() self.resampler.update_weights(self.D) else: continue_boosting = not self.early_stopping alpha = 1. / (self.member_number + 1) self.alphas.append(alpha) self.member_number += 1 return (m.to_yaml(), m.get_weights(), continue_boosting)
def create_member(self): self.set_defaults() train_set, sample_weights = self.resampler.make_new_train( self.params.resample_size) if self.member_number > 0: if self.resample: resampled = [ train_set, self.resampler.get_valid(), self.resampler.get_test() ] else: resampled = [ self.resampler.get_train(), self.resampler.get_valid(), self.resampler.get_test() ] else: sample_weights = None resampled = [ self.resampler.get_train(), self.resampler.get_valid(), self.resampler.get_test() ] if self.member_number > 0: self.params.n_epochs = self.n_epochs_after_first if 'lr_after_first' in self.params.__dict__: self.params.optimizer['config'][ 'lr'] = self.params.lr_after_first if not self.use_sample_weights: sample_weights = None m = mlp.sequential_model( resampled, self.params, member_number=self.member_number, model_weights=self.weights, #the copy is because there is a bug in Keras that deletes names model_config=copy.deepcopy(self.model_config), sample_weight=sample_weights) self.weights = [l.get_weights() for l in m.layers] injection_index = self.incremental_index + self.member_number * len( self.incremental_layers) if self.incremental_layers is not None: if injection_index == -1: injection_index = len(self.model_config) new_layers = [] for i, l in enumerate(self.incremental_layers): l['config']['name'] = "DIB-incremental-{0}-{1}".format( self.member_number, i) new_layers.append(l) new_model_config = self.model_config[: injection_index] + new_layers + self.model_config[ injection_index:] self.model_config = copy.deepcopy(new_model_config) self.weights = self.weights[:injection_index] orig_train = self.resampler.get_train() K = orig_train[1].shape[1] errors = common.errors(m, orig_train[0], orig_train[1]) e = sum((errors * self.D)) / sum(errors + np.finfo(np.float32).eps) alpha = math.log((1 - e) / e + np.finfo(np.float32).eps) + math.log(K - 1) w = np.where(errors == 1, self.D * math.exp(alpha), self.D * math.exp(-alpha)) self.D = w / w.sum() self.resampler.update_weights(self.D) self.alphas.append(alpha) self.member_number += 1 m_yaml = m.to_yaml() m_weights = m.get_weights() del m return (m_yaml, m_weights)