def main(_): predict()
def train(): print("Preparing dialog data in %s" % FLAGS.data_dir) train_data, dev_data, _ = data_utils.prepare_dialog_data(FLAGS.data_dir, FLAGS.vocab_size) with tf.Session() as sess: # Create model. print("Creating %d layers of %d units." % (FLAGS.num_layers, FLAGS.size)) model = create_model(sess, forward_only=False) # Read data into buckets and compute their sizes. print ("Reading development and training data (limit: %d)." % FLAGS.max_train_data_size) dev_set = read_data(dev_data) train_set = read_data(train_data, FLAGS.max_train_data_size) train_bucket_sizes = [len(train_set[b]) for b in xrange(len(BUCKETS))] train_total_size = float(sum(train_bucket_sizes)) # A bucket scale is a list of increasing numbers from 0 to 1 that we'll use # to select a bucket. Length of [scale[i], scale[i+1]] is proportional to # the size if i-th training bucket, as used later. train_buckets_scale = [sum(train_bucket_sizes[:i + 1]) / train_total_size for i in xrange(len(train_bucket_sizes))] # This is the training loop. step_time, loss = 0.0, 0.0 current_step = 0 previous_losses = [] while True: # Choose a bucket according to data distribution. We pick a random number # in [0, 1] and use the corresponding interval in train_buckets_scale. random_number_01 = np.random.random_sample() bucket_id = min([i for i in xrange(len(train_buckets_scale)) if train_buckets_scale[i] > random_number_01]) # Get a batch and make a step. start_time = time.time() encoder_inputs, decoder_inputs, target_weights = model.get_batch( train_set, bucket_id) # TODO: why gradient_norm isn't used here? _, step_loss, _ = model.step(sess, encoder_inputs, decoder_inputs, target_weights, bucket_id, forward_only=False) step_time += (time.time() - start_time) / FLAGS.steps_per_checkpoint loss += step_loss / FLAGS.steps_per_checkpoint current_step += 1 # Once in a while, we save checkpoint, print statistics, and run evals. if current_step % FLAGS.steps_per_checkpoint == 0: # Print statistics for the previous epoch. perplexity = math.exp(loss) if loss < 300 else float('inf') print ("global step %d learning rate %.4f step-time %.2f perplexity %.2f" % (model.global_step.eval(), model.learning_rate.eval(), step_time, perplexity)) # Decrease learning rate if no improvement was seen over last 3 times. if len(previous_losses) > 2 and loss > max(previous_losses[-3:]): sess.run(model.learning_rate_decay_op) previous_losses.append(loss) # Save checkpoint and zero timer and loss. checkpoint_path = os.path.join(FLAGS.model_dir, "model.ckpt") model.saver.save(sess, checkpoint_path, global_step=model.global_step) step_time, loss = 0.0, 0.0 # Run evals on development set and print their perplexity. for bucket_id in xrange(len(BUCKETS)): encoder_inputs, decoder_inputs, target_weights = model.get_batch(dev_set, bucket_id) _, eval_loss, _ = model.step(sess, encoder_inputs, decoder_inputs, target_weights, bucket_id, True) eval_ppx = math.exp(eval_loss) if eval_loss < 300 else float('inf') print(" eval: bucket %d perplexity %.2f" % (bucket_id, eval_ppx)) sys.stdout.flush() # Print prediction results for the test set predict.predict()