# Library The example notebook (available [here](https://github.com/OpenNMT/OpenNMT-py/blob/master/docs/source/examples/Library.ipynb)) should be able to run as a standalone execution, provided `onmt` is in the path (installed via `pip` for instance). Some parts may not be 100% 'library-friendly' but it's mostly workable. ### Import a few modules and functions that will be necessary ```python import yaml import torch import torch.nn as nn from argparse import Namespace from collections import defaultdict, Counter ``` ```python import onmt from onmt.inputters.inputter import _load_vocab, _build_fields_vocab, get_fields, IterOnDevice from onmt.inputters.corpus import ParallelCorpus from onmt.inputters.dynamic_iterator import DynamicDatasetIter from onmt.translate import GNMTGlobalScorer, Translator, TranslationBuilder from onmt.utils.misc import set_random_seed ``` ### Enable logging ```python # enable logging from onmt.utils.logging import init_logger, logger init_logger() ``` ### Set random seed ```python is_cuda = torch.cuda.is_available() set_random_seed(1111, is_cuda) ``` ### Retrieve data To make a proper example, we will need some data, as well as some vocabulary(ies). Let's take the same data as in the [quickstart](https://opennmt.net/OpenNMT-py/quickstart.html): ```python !wget https://s3.amazonaws.com/opennmt-trainingdata/toy-ende.tar.gz ``` --2020-09-25 15:28:05-- https://s3.amazonaws.com/opennmt-trainingdata/toy-ende.tar.gz Resolving s3.amazonaws.com (s3.amazonaws.com)... 52.217.18.38 Connecting to s3.amazonaws.com (s3.amazonaws.com)|52.217.18.38|:443... connected. HTTP request sent, awaiting response... 200 OK Length: 1662081 (1,6M) [application/x-gzip] Saving to: ‘toy-ende.tar.gz.5’ toy-ende.tar.gz.5 100%[===================>] 1,58M 2,33MB/s in 0,7s 2020-09-25 15:28:07 (2,33 MB/s) - ‘toy-ende.tar.gz.5’ saved [1662081/1662081] ```python !tar xf toy-ende.tar.gz ``` ```python ls toy-ende ``` config.yaml src-test.txt src-val.txt tgt-train.txt run/ src-train.txt tgt-test.txt tgt-val.txt ### Prepare data and vocab As for any use case of OpenNMT-py 2.0, we can start by creating a simple YAML configuration with our datasets. This is the easiest way to build the proper `opts` `Namespace` that will be used to create the vocabulary(ies). ```python yaml_config = """ ## Where the samples will be written save_data: toy-ende/run/example ## Where the vocab(s) will be written src_vocab: toy-ende/run/example.vocab.src tgt_vocab: toy-ende/run/example.vocab.tgt # Corpus opts: data: corpus: path_src: toy-ende/src-train.txt path_tgt: toy-ende/tgt-train.txt transforms: [] weight: 1 valid: path_src: toy-ende/src-val.txt path_tgt: toy-ende/tgt-val.txt transforms: [] """ config = yaml.safe_load(yaml_config) with open("toy-ende/config.yaml", "w") as f: f.write(yaml_config) ``` ```python from onmt.utils.parse import ArgumentParser parser = DynamicArgumentParser(description='build_vocab.py') ``` ```python from onmt.opts import dynamic_prepare_opts dynamic_prepare_opts(parser, build_vocab_only=True) ``` ```python base_args = (["-config", "toy-ende/config.yaml", "-n_sample", "10000"]) opts, unknown = parser.parse_known_args(base_args) ``` ```python opts ``` Namespace(config='toy-ende/config.yaml', data="{'corpus': {'path_src': 'toy-ende/src-train.txt', 'path_tgt': 'toy-ende/tgt-train.txt', 'transforms': [], 'weight': 1}, 'valid': {'path_src': 'toy-ende/src-val.txt', 'path_tgt': 'toy-ende/tgt-val.txt', 'transforms': []}}", insert_ratio=0.0, mask_length='subword', mask_ratio=0.0, n_sample=10000, src_onmttok_kwargs="{'mode': 'none'}", tgt_onmttok_kwargs="{'mode': 'none'}", overwrite=False, permute_sent_ratio=0.0, poisson_lambda=0.0, random_ratio=0.0, replace_length=-1, rotate_ratio=0.5, save_config=None, save_data='toy-ende/run/example', seed=-1, share_vocab=False, skip_empty_level='warning', src_seq_length=200, src_subword_model=None, src_subword_type='none', src_vocab=None, subword_alpha=0, subword_nbest=1, switchout_temperature=1.0, tgt_seq_length=200, tgt_subword_model=None, tgt_subword_type='none', tgt_vocab=None, tokendrop_temperature=1.0, tokenmask_temperature=1.0, transforms=[]) ```python from onmt.bin.build_vocab import build_vocab_main build_vocab_main(opts) ``` [2020-09-25 15:28:08,068 INFO] Parsed 2 corpora from -data. [2020-09-25 15:28:08,069 INFO] Counter vocab from 10000 samples. [2020-09-25 15:28:08,070 INFO] Save 10000 transformed example/corpus. [2020-09-25 15:28:08,070 INFO] corpus's transforms: TransformPipe() [2020-09-25 15:28:08,101 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:28:08,320 INFO] Just finished the first loop [2020-09-25 15:28:08,320 INFO] Counters src:24995 [2020-09-25 15:28:08,321 INFO] Counters tgt:35816 ```python ls toy-ende/run ``` example.vocab.src example.vocab.tgt sample/ We just created our source and target vocabularies, respectively `toy-ende/run/example.vocab.src` and `toy-ende/run/example.vocab.tgt`. ### Build fields We can build the fields from the text files that were just created. ```python src_vocab_path = "toy-ende/run/example.vocab.src" tgt_vocab_path = "toy-ende/run/example.vocab.tgt" ``` ```python # initialize the frequency counter counters = defaultdict(Counter) # load source vocab _src_vocab, _src_vocab_size = _load_vocab( src_vocab_path, 'src', counters) # load target vocab _tgt_vocab, _tgt_vocab_size = _load_vocab( tgt_vocab_path, 'tgt', counters) ``` [2020-09-25 15:28:08,495 INFO] Loading src vocabulary from toy-ende/run/example.vocab.src [2020-09-25 15:28:08,554 INFO] Loaded src vocab has 24995 tokens. [2020-09-25 15:28:08,562 INFO] Loading tgt vocabulary from toy-ende/run/example.vocab.tgt [2020-09-25 15:28:08,617 INFO] Loaded tgt vocab has 35816 tokens. ```python # initialize fields src_nfeats, tgt_nfeats = 0, 0 # do not support word features for now fields = get_fields( 'text', src_nfeats, tgt_nfeats) ``` ```python fields ``` {'src': , 'tgt': , 'indices': } ```python # build fields vocab share_vocab = False vocab_size_multiple = 1 src_vocab_size = 30000 tgt_vocab_size = 30000 src_words_min_frequency = 1 tgt_words_min_frequency = 1 vocab_fields = _build_fields_vocab( fields, counters, 'text', share_vocab, vocab_size_multiple, src_vocab_size, src_words_min_frequency, tgt_vocab_size, tgt_words_min_frequency) ``` [2020-09-25 15:28:08,699 INFO] * tgt vocab size: 30004. [2020-09-25 15:28:08,749 INFO] * src vocab size: 24997. An alternative way of creating these fields is to run `onmt_train` without actually training, to just output the necessary files. ### Prepare for training: model and optimizer creation Let's get a few fields/vocab related variables to simplify the model creation a bit: ```python src_text_field = vocab_fields["src"].base_field src_vocab = src_text_field.vocab src_padding = src_vocab.stoi[src_text_field.pad_token] tgt_text_field = vocab_fields['tgt'].base_field tgt_vocab = tgt_text_field.vocab tgt_padding = tgt_vocab.stoi[tgt_text_field.pad_token] ``` Next we specify the core model itself. Here we will build a small model with an encoder and an attention based input feeding decoder. Both models will be RNNs and the encoder will be bidirectional ```python emb_size = 100 rnn_size = 500 # Specify the core model. encoder_embeddings = onmt.modules.Embeddings(emb_size, len(src_vocab), word_padding_idx=src_padding) encoder = onmt.encoders.RNNEncoder(hidden_size=rnn_size, num_layers=1, rnn_type="LSTM", bidirectional=True, embeddings=encoder_embeddings) decoder_embeddings = onmt.modules.Embeddings(emb_size, len(tgt_vocab), word_padding_idx=tgt_padding) decoder = onmt.decoders.decoder.InputFeedRNNDecoder( hidden_size=rnn_size, num_layers=1, bidirectional_encoder=True, rnn_type="LSTM", embeddings=decoder_embeddings) device = "cuda" if torch.cuda.is_available() else "cpu" model = onmt.models.model.NMTModel(encoder, decoder) model.to(device) # Specify the tgt word generator and loss computation module model.generator = nn.Sequential( nn.Linear(rnn_size, len(tgt_vocab)), nn.LogSoftmax(dim=-1)).to(device) loss = onmt.utils.loss.NMTLossCompute( criterion=nn.NLLLoss(ignore_index=tgt_padding, reduction="sum"), generator=model.generator) ``` Now we set up the optimizer. This could be a core torch optim class, or our wrapper which handles learning rate updates and gradient normalization automatically. ```python lr = 1 torch_optimizer = torch.optim.SGD(model.parameters(), lr=lr) optim = onmt.utils.optimizers.Optimizer( torch_optimizer, learning_rate=lr, max_grad_norm=2) ``` ### Create the training and validation data iterators Now we need to create the dynamic dataset iterator. This is not very 'library-friendly' for now because of the way the `DynamicDatasetIter` constructor is defined. It may evolve in the future. ```python src_train = "toy-ende/src-train.txt" tgt_train = "toy-ende/tgt-train.txt" src_val = "toy-ende/src-val.txt" tgt_val = "toy-ende/tgt-val.txt" # build the ParallelCorpus corpus = ParallelCorpus("corpus", src_train, tgt_train) valid = ParallelCorpus("valid", src_val, tgt_val) ``` ```python # build the training iterator train_iter = DynamicDatasetIter( corpora={"corpus": corpus}, corpora_info={"corpus": {"weight": 1}}, transforms={}, fields=vocab_fields, is_train=True, batch_type="tokens", batch_size=4096, batch_size_multiple=1, data_type="text") ``` ```python # make sure the iteration happens on GPU 0 (-1 for CPU, N for GPU N) train_iter = iter(IterOnDevice(train_iter, 0)) ``` ```python # build the validation iterator valid_iter = DynamicDatasetIter( corpora={"valid": valid}, corpora_info={"valid": {"weight": 1}}, transforms={}, fields=vocab_fields, is_train=False, batch_type="sents", batch_size=8, batch_size_multiple=1, data_type="text") ``` ```python valid_iter = IterOnDevice(valid_iter, 0) ``` ### Training Finally we train. ```python report_manager = onmt.utils.ReportMgr( report_every=50, start_time=None, tensorboard_writer=None) trainer = onmt.Trainer(model=model, train_loss=loss, valid_loss=loss, optim=optim, report_manager=report_manager, dropout=[0.1]) trainer.train(train_iter=train_iter, train_steps=1000, valid_iter=valid_iter, valid_steps=500) ``` [2020-09-25 15:28:15,184 INFO] Start training loop and validate every 500 steps... [2020-09-25 15:28:15,185 INFO] corpus's transforms: TransformPipe() [2020-09-25 15:28:15,187 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:28:21,140 INFO] Step 50/ 1000; acc: 7.52; ppl: 8832.29; xent: 9.09; lr: 1.00000; 18916/18871 tok/s; 6 sec [2020-09-25 15:28:24,869 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:28:27,121 INFO] Step 100/ 1000; acc: 9.34; ppl: 1840.06; xent: 7.52; lr: 1.00000; 18911/18785 tok/s; 12 sec [2020-09-25 15:28:33,048 INFO] Step 150/ 1000; acc: 10.35; ppl: 1419.18; xent: 7.26; lr: 1.00000; 19062/19017 tok/s; 18 sec [2020-09-25 15:28:37,019 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:28:39,022 INFO] Step 200/ 1000; acc: 11.14; ppl: 1127.44; xent: 7.03; lr: 1.00000; 19084/18911 tok/s; 24 sec [2020-09-25 15:28:45,073 INFO] Step 250/ 1000; acc: 12.46; ppl: 912.13; xent: 6.82; lr: 1.00000; 18575/18570 tok/s; 30 sec [2020-09-25 15:28:49,301 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:28:51,151 INFO] Step 300/ 1000; acc: 13.04; ppl: 779.50; xent: 6.66; lr: 1.00000; 18394/18307 tok/s; 36 sec [2020-09-25 15:28:57,316 INFO] Step 350/ 1000; acc: 14.04; ppl: 685.48; xent: 6.53; lr: 1.00000; 18339/18173 tok/s; 42 sec [2020-09-25 15:29:02,117 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:29:03,576 INFO] Step 400/ 1000; acc: 14.99; ppl: 590.20; xent: 6.38; lr: 1.00000; 18090/18029 tok/s; 48 sec [2020-09-25 15:29:09,546 INFO] Step 450/ 1000; acc: 16.00; ppl: 524.51; xent: 6.26; lr: 1.00000; 18726/18536 tok/s; 54 sec [2020-09-25 15:29:14,585 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:29:15,596 INFO] Step 500/ 1000; acc: 16.78; ppl: 453.38; xent: 6.12; lr: 1.00000; 17877/17980 tok/s; 60 sec [2020-09-25 15:29:15,597 INFO] valid's transforms: TransformPipe() [2020-09-25 15:29:15,599 INFO] Loading ParallelCorpus(toy-ende/src-val.txt, toy-ende/tgt-val.txt, align=None)... [2020-09-25 15:29:24,528 INFO] Validation perplexity: 295.1 [2020-09-25 15:29:24,529 INFO] Validation accuracy: 17.6533 [2020-09-25 15:29:30,592 INFO] Step 550/ 1000; acc: 17.47; ppl: 421.26; xent: 6.04; lr: 1.00000; 7726/7610 tok/s; 75 sec [2020-09-25 15:29:36,055 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:29:36,695 INFO] Step 600/ 1000; acc: 18.95; ppl: 354.44; xent: 5.87; lr: 1.00000; 17470/17598 tok/s; 82 sec [2020-09-25 15:29:42,794 INFO] Step 650/ 1000; acc: 19.60; ppl: 328.47; xent: 5.79; lr: 1.00000; 18994/18793 tok/s; 88 sec [2020-09-25 15:29:48,635 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:29:48,924 INFO] Step 700/ 1000; acc: 20.57; ppl: 285.48; xent: 5.65; lr: 1.00000; 17856/17788 tok/s; 94 sec [2020-09-25 15:29:54,898 INFO] Step 750/ 1000; acc: 21.97; ppl: 249.06; xent: 5.52; lr: 1.00000; 19030/18924 tok/s; 100 sec [2020-09-25 15:30:01,233 INFO] Step 800/ 1000; acc: 22.66; ppl: 228.54; xent: 5.43; lr: 1.00000; 17571/17471 tok/s; 106 sec [2020-09-25 15:30:01,357 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:30:07,345 INFO] Step 850/ 1000; acc: 24.32; ppl: 193.65; xent: 5.27; lr: 1.00000; 18344/18313 tok/s; 112 sec [2020-09-25 15:30:11,363 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:30:13,487 INFO] Step 900/ 1000; acc: 24.93; ppl: 177.65; xent: 5.18; lr: 1.00000; 18293/18105 tok/s; 118 sec [2020-09-25 15:30:19,670 INFO] Step 950/ 1000; acc: 26.33; ppl: 157.10; xent: 5.06; lr: 1.00000; 17791/17746 tok/s; 124 sec [2020-09-25 15:30:24,072 INFO] Loading ParallelCorpus(toy-ende/src-train.txt, toy-ende/tgt-train.txt, align=None)... [2020-09-25 15:30:25,820 INFO] Step 1000/ 1000; acc: 27.47; ppl: 137.64; xent: 4.92; lr: 1.00000; 17942/17962 tok/s; 131 sec [2020-09-25 15:30:25,822 INFO] Loading ParallelCorpus(toy-ende/src-val.txt, toy-ende/tgt-val.txt, align=None)... [2020-09-25 15:30:34,665 INFO] Validation perplexity: 241.801 [2020-09-25 15:30:34,666 INFO] Validation accuracy: 20.2837 ### Translate For translation, we can build a "traditional" (as opposed to dynamic) dataset for now. ```python src_data = {"reader": onmt.inputters.str2reader["text"](), "data": src_val} tgt_data = {"reader": onmt.inputters.str2reader["text"](), "data": tgt_val} _readers, _data = onmt.inputters.Dataset.config( [('src', src_data), ('tgt', tgt_data)]) ``` ```python dataset = onmt.inputters.Dataset( vocab_fields, readers=_readers, data=_data, sort_key=onmt.inputters.str2sortkey["text"]) ``` ```python data_iter = onmt.inputters.OrderedIterator( dataset=dataset, device="cuda", batch_size=10, train=False, sort=False, sort_within_batch=True, shuffle=False ) ``` ```python src_reader = onmt.inputters.str2reader["text"] tgt_reader = onmt.inputters.str2reader["text"] scorer = GNMTGlobalScorer(alpha=0.7, beta=0., length_penalty="avg", coverage_penalty="none") gpu = 0 if torch.cuda.is_available() else -1 translator = Translator(model=model, fields=vocab_fields, src_reader=src_reader, tgt_reader=tgt_reader, global_scorer=scorer, gpu=gpu) builder = onmt.translate.TranslationBuilder(data=dataset, fields=vocab_fields) ``` **Note**: translations will be very poor, because of the very low quantity of data, the absence of proper tokenization, and the brevity of the training. ```python for batch in data_iter: trans_batch = translator.translate_batch( batch=batch, src_vocabs=[src_vocab], attn_debug=False) translations = builder.from_batch(trans_batch) for trans in translations: print(trans.log(0)) break ``` SENT 0: ['Parliament', 'Does', 'Not', 'Support', 'Amendment', 'Freeing', 'Tymoshenko'] PRED 0: Parlament das Parlament über die Europäische Parlament , die sich in der Lage in der Lage ist , die es in der Lage sind . PRED SCORE: -1.5935 SENT 0: ['Today', ',', 'the', 'Ukraine', 'parliament', 'dismissed', ',', 'within', 'the', 'Code', 'of', 'Criminal', 'Procedure', 'amendment', ',', 'the', 'motion', 'to', 'revoke', 'an', 'article', 'based', 'on', 'which', 'the', 'opposition', 'leader', ',', 'Yulia', 'Tymoshenko', ',', 'was', 'sentenced', '.'] PRED 0: In der Nähe des Hotels , die in der Lage , die sich in der Lage ist , in der Lage , die in der Lage , die in der Lage ist . PRED SCORE: -1.7173 SENT 0: ['The', 'amendment', 'that', 'would', 'lead', 'to', 'freeing', 'the', 'imprisoned', 'former', 'Prime', 'Minister', 'was', 'revoked', 'during', 'second', 'reading', 'of', 'the', 'proposal', 'for', 'mitigation', 'of', 'sentences', 'for', 'economic', 'offences', '.'] PRED 0: Die Tatsache , die sich in der Lage in der Lage ist , die für eine Antwort der Entwicklung für die Entwicklung von Präsident . PRED SCORE: -1.6834 SENT 0: ['In', 'October', ',', 'Tymoshenko', 'was', 'sentenced', 'to', 'seven', 'years', 'in', 'prison', 'for', 'entering', 'into', 'what', 'was', 'reported', 'to', 'be', 'a', 'disadvantageous', 'gas', 'deal', 'with', 'Russia', '.'] PRED 0: In der Nähe wurde die Menschen in der Lage ist , die sich in der Lage . PRED SCORE: -1.5765 SENT 0: ['The', 'verdict', 'is', 'not', 'yet', 'final;', 'the', 'court', 'will', 'hear', 'Tymoshenko', ''s', 'appeal', 'in', 'December', '.'] PRED 0: Es ist nicht der Fall , die in der Lage in der Lage sind . PRED SCORE: -1.3287 SENT 0: ['Tymoshenko', 'claims', 'the', 'verdict', 'is', 'a', 'political', 'revenge', 'of', 'the', 'regime;', 'in', 'the', 'West', ',', 'the', 'trial', 'has', 'also', 'evoked', 'suspicion', 'of', 'being', 'biased', '.'] PRED 0: Um in der Lage ist auch eine Lösung Rolle . PRED SCORE: -1.3975 SENT 0: ['The', 'proposal', 'to', 'remove', 'Article', '365', 'from', 'the', 'Code', 'of', 'Criminal', 'Procedure', ',', 'upon', 'which', 'the', 'former', 'Prime', 'Minister', 'was', 'sentenced', ',', 'was', 'supported', 'by', '147', 'members', 'of', 'parliament', '.'] PRED 0: Der Vorschlag , die in der Lage , die in der Lage , die in der Lage ist , war er von der Fall wurde . PRED SCORE: -1.6062 SENT 0: ['Its', 'ratification', 'would', 'require', '226', 'votes', '.'] PRED 0: Es wäre noch einmal noch einmal . PRED SCORE: -1.8001 SENT 0: ['Libya', ''s', 'Victory'] PRED 0: In der Nähe des Hotels befindet sich in der Nähe des Hotels in der Lage . PRED SCORE: -1.7097 SENT 0: ['The', 'story', 'of', 'Libya', ''s', 'liberation', ',', 'or', 'rebellion', ',', 'already', 'has', 'its', 'defeated', '.'] PRED 0: In der Nähe des Hotels in der Lage ist in der Lage . PRED SCORE: -1.7885