# edit-mode: -*- python -*- # Copyright (c) 2016 Baidu, Inc. All Rights Reserved # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. import sys import os from paddle.trainer_config_helpers import * def seq_to_seq_data(data_dir, is_generating, dict_size=30000, train_list='train.list', test_list='test.list', gen_list='gen.list', gen_result='gen_result'): """ Predefined seqToseq train data provider for application is_generating: whether this config is used for generating dict_size: word count of dictionary train_list: a text file containing a list of training data test_list: a text file containing a list of testing data gen_list: a text file containing a list of generating data gen_result: a text file containing generating result """ src_lang_dict = os.path.join(data_dir, 'src.dict') trg_lang_dict = os.path.join(data_dir, 'trg.dict') src_dict = dict() for line_count, line in enumerate(open(src_lang_dict, "r")): src_dict[line.strip()] = line_count trg_dict = dict() for line_count, line in enumerate(open(trg_lang_dict, "r")): trg_dict[line.strip()] = line_count if is_generating: train_list = None test_list = os.path.join(data_dir, gen_list) trg_dict = None else: train_list = os.path.join(data_dir, train_list) test_list = os.path.join(data_dir,test_list) define_py_data_sources2(train_list, test_list, module = "dataprovider", obj = "process", args = {"src_dict": src_dict, "trg_dict": trg_dict}) return {"src_dict_path": src_lang_dict, "trg_dict_path": trg_lang_dict, "gen_result": gen_result} def gru_encoder_decoder(data_conf, is_generating, word_vector_dim=512, encoder_size=512, decoder_size=512, beam_size=3, max_length=250): """ A wrapper for an attention version of GRU Encoder-Decoder network is_generating: whether this config is used for generating encoder_size: dimension of hidden unit in GRU Encoder network decoder_size: dimension of hidden unit in GRU Decoder network word_vector_dim: dimension of word vector beam_size: expand width in beam search max_length: a stop condition of sequence generation """ for k, v in data_conf.iteritems(): globals()[k] = v source_dict_dim = len(open(src_dict_path, "r").readlines()) target_dict_dim = len(open(trg_dict_path, "r").readlines()) gen_trans_file = gen_result src_word_id = data_layer(name='source_language_word', size=source_dict_dim) src_embedding = embedding_layer( input=src_word_id, size=word_vector_dim, param_attr=ParamAttr(name='_source_language_embedding'), ) src_forward = simple_gru(input=src_embedding, size=encoder_size, ) src_backward = simple_gru(input=src_embedding, size=encoder_size, reverse=True, ) encoded_vector = concat_layer(input=[src_forward, src_backward]) with mixed_layer(size=decoder_size) as encoded_proj: encoded_proj += full_matrix_projection(encoded_vector) backward_first = first_seq(input=src_backward) with mixed_layer(size=decoder_size, act=TanhActivation(), ) as decoder_boot: decoder_boot += full_matrix_projection(backward_first) def gru_decoder_with_attention(enc_vec, enc_proj, current_word): decoder_mem = memory(name='gru_decoder', size=decoder_size, boot_layer=decoder_boot) context = simple_attention(encoded_sequence=enc_vec, encoded_proj=enc_proj, decoder_state=decoder_mem, ) with mixed_layer(size=decoder_size * 3) as decoder_inputs: decoder_inputs += full_matrix_projection(context) decoder_inputs += full_matrix_projection(current_word) gru_step = gru_step_layer(name='gru_decoder', input=decoder_inputs, output_mem=decoder_mem, size=decoder_size) with mixed_layer(size=target_dict_dim, bias_attr=True, act=SoftmaxActivation()) as out: out += full_matrix_projection(input=gru_step) return out decoder_group_name = "decoder_group" if not is_generating: trg_embedding = embedding_layer( input=data_layer(name='target_language_word', size=target_dict_dim), size=word_vector_dim, param_attr=ParamAttr(name='_target_language_embedding')) # For decoder equipped with attention mechanism, in training, # target embeding (the groudtruth) is the data input, # while encoded source sequence is accessed to as an unbounded memory. # Here, the StaticInput defines a read-only memory # for the recurrent_group. decoder = recurrent_group(name=decoder_group_name, step=gru_decoder_with_attention, input=[ StaticInput(input=encoded_vector, is_seq=True), StaticInput(input=encoded_proj, is_seq=True), trg_embedding ], ) lbl = data_layer(name='target_language_next_word', size=target_dict_dim) cost = classification_cost(input=decoder, label=lbl, ) outputs(cost) else: gen_inputs = [StaticInput(input=encoded_vector, is_seq=True), StaticInput(input=encoded_proj, is_seq=True), ] # In generation, decoder predicts a next target word based on # the encoded source sequence and the last generated target word. # The encoded source sequence (encoder's output) must be specified by # StaticInput which is a read-only memory. # Here, GeneratedInputs automatically fetchs the last generated word, # which is initialized by a start mark, such as . trg_embedding = GeneratedInput( size=target_dict_dim, embedding_name='_target_language_embedding', embedding_size=word_vector_dim) gen_inputs.append(trg_embedding) beam_gen = beam_search(name=decoder_group_name, step=gru_decoder_with_attention, input=gen_inputs, id_input=data_layer(name="sent_id", size=1), dict_file=trg_dict_path, bos_id=0, eos_id=1, beam_size=beam_size, max_length=max_length, result_file=gen_trans_file) outputs(beam_gen)