Merge pull request #74 from tensorflow/neural-translation

Continue working on neural translation model #9. Added language model example #64

examples/README.md

@@ -1,5 +1,4 @@
-Examples of Using skflow
-========================
+# Examples of Using skflow
 
 * [Deep Neural Network Regression with Boston Data](boston.py)
 * [Convolutional Neural Networks with Digits Data](digits.py)
@@ -14,19 +13,28 @@ Examples of Using skflow
 * [Out-of-core Data Classification Using Dask](out_of_core_data_classification.py)
 
 
-Image classification
---------------------
+## Image classification
 
 * [Convolutional Neural Networks on MNIST Data](mnist.py)
 * [Deep Residual Networks on MNIST Data](resnet.py)
 
 
-Text classification
--------------------
+## Text classification
 
 * [Text Classification Using Recurrent Neural Networks on Words](text_classification.py) 
 (See also [Simplified Version Using Built-in RNN Model](text_classification_builtin_rnn_model.py) with easy to use built-in parameters)
 * [Text Classification Using Convolutional Neural Networks on Words](text_classification_cnn.py)
 * [Text Classification Using Recurrent Neural Networks on Characters](text_classification_character_rnn.py)
 * [Text Classification Using Convolutional Neural Networks on Characters](text_classification_character_cnn.py)
 
+
+## Language modeling
+
+* [Character level language modeling](language_model.py)
+
+
+## Text sequence to sequence
+
+* [Character level neural language translation](neural_translation.py)
+* [Word level neural language translation](neural_translation_word.py)
+

examples/language_model.py

@@ -0,0 +1,102 @@
+# encoding: utf-8
+
+#  Copyright 2015-present Scikit Flow Authors. 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.
+
+from __future__ import division, print_function, absolute_import
+
+import itertools
+import math
+import os
+import numpy as np
+
+import tensorflow as tf
+
+import skflow
+
+### Training data
+
+CORPUS_FILENAME = "europarl-v6.fr-en.en"
+MAX_DOC_LENGTH = 10
+
+def training_data(filename):
+    f = open(filename)
+    for line in f:
+        yield line
+
+
+def iter_docs(docs):
+  for doc in docs:
+    n_parts = int(math.ceil(float(len(doc)) / MAX_DOC_LENGTH))
+    for part in range(n_parts):
+      offset_begin = part * MAX_DOC_LENGTH
+      offset_end = offset_begin + MAX_DOC_LENGTH
+      inp = np.zeros(MAX_DOC_LENGTH, dtype=np.int32)
+      out = np.zeros(MAX_DOC_LENGTH, dtype=np.int32)
+      inp[:min(offset_end - offset_begin, len(doc) - offset_begin)] = doc[offset_begin:offset_end]
+      out[:min(offset_end - offset_begin, len(doc) - offset_begin - 1)] = doc[offset_begin + 1:offset_end + 1]
+      yield inp, out
+
+
+def unpack_xy(iter_obj):
+  X, y = itertools.tee(iter_obj)
+  return (item[0] for item in X), (item[1] for item in y)
+
+
+byte_processor = skflow.preprocessing.ByteProcessor(
+    max_document_length=MAX_DOC_LENGTH)
+
+data = training_data(CORPUS_FILENAME)
+data = byte_processor.transform(data)
+X, y = unpack_xy(iter_docs(data))
+
+
+### Model
+
+HIDDEN_SIZE = 10
+
+
+def seq_autoencoder(X, y):
+    """Sequence auto-encoder with RNN."""
+    inputs = skflow.ops.one_hot_matrix(X, 256)
+    in_X, in_y, out_y = skflow.ops.seq2seq_inputs(inputs, y, MAX_DOC_LENGTH, MAX_DOC_LENGTH)
+    encoder_cell = tf.nn.rnn_cell.GRUCell(HIDDEN_SIZE)
+    decoder_cell = tf.nn.rnn_cell.OutputProjectionWrapper(tf.nn.rnn_cell.GRUCell(HIDDEN_SIZE), 256)
+    decoding, _, sampling_decoding, _ = skflow.ops.rnn_seq2seq(in_X, in_y, encoder_cell, decoder_cell)
+    return skflow.ops.sequence_classifier(decoding, out_y, sampling_decoding)
+
+
+def get_language_model(hidden_size):
+    """Returns a language model with given hidden size."""
+
+    def language_model(X, y):
+        inputs = skflow.ops.one_hot_matrix(X, 256)
+        inputs = skflow.ops.split_squeeze(1, MAX_DOC_LENGTH, inputs)
+        target = skflow.ops.split_squeeze(1, MAX_DOC_LENGTH, y)
+        encoder_cell = tf.nn.rnn_cell.OutputProjectionWrapper(tf.nn.rnn_cell.GRUCell(hidden_size),256)
+        output, _ = tf.nn.rnn(encoder_cell, inputs, dtype=tf.float32)
+        return skflow.ops.sequence_classifier(output, target)
+
+    return language_model
+
+
+### Training model.
+
+estimator = skflow.TensorFlowEstimator(model_fn=get_language_model(HIDDEN_SIZE), 
+                                       n_classes=256, 
+                                       optimizer='Adam', learning_rate=0.01, 
+                                       steps=1000, batch_size=64, continue_training=True)
+
+estimator.fit(X, y)
+

examples/neural_translation.py

@@ -16,88 +16,103 @@
 
 from __future__ import division, print_function, absolute_import
 
+import itertools
 import os
 import numpy as np
 
 import tensorflow as tf
-from tensorflow.python.ops import rnn_cell, rnn, seq2seq
 
 import skflow
 
 # Get training data
 
 # This dataset can be downloaded from http://www.statmt.org/europarl/v6/fr-en.tgz
 
-def X_iter():
+ENGLISH_CORPUS = "europarl-v6.fr-en.en"
+FRENCH_CORPUS = "europarl-v6.fr-en.fr"
+
+def read_iterator(filename):
+    f = open(filename)
+    for line in f:
+        yield line.strip()
+
+
+def repeated_read_iterator(filename):
     while True:
-        yield "some sentence"
-        yield "some other sentence"
+        f = open(filename)
+        for line in f:
+            yield line.strip()
+
+
+def split_train_test(data, partition=0.2, random_seed=42):
+    rnd = np.random.RandomState(random_seed)
+    for item in data:
+        if rnd.uniform() > partition:
+            yield (0, item)
+        else:
+            yield (1, item)
+
+
+def save_partitions(data, filenames):
+    files = [open(filename, 'w') for filename in filenames]
+    for partition, item in data:
+        files[partition].write(item + '\n')
 
-X_pred = ["some sentence", "some other sentence"]
 
-def y_iter():
+def loop_iterator(data):
     while True:
-        yield "какое-то приложение"
-        yield "какое-то другое приложение"
+        for item in data:
+            yield item
 
-# Translation model
 
-MAX_DOCUMENT_LENGTH = 10
-HIDDEN_SIZE = 10
-
-def rnn_decoder(decoder_inputs, initial_state, cell, scope=None):
-    with tf.variable_scope(scope or "dnn_decoder"):
-        states, sampling_states = [initial_state], [initial_state]
-        outputs, sampling_outputs = [], []
-        with tf.op_scope([decoder_inputs, initial_state], "training"):
-            for i in xrange(len(decoder_inputs)):
-                inp = decoder_inputs[i]
-                if i > 0:
-                    tf.get_variable_scope().reuse_variables()
-                output, new_state = cell(inp, states[-1])
-                outputs.append(output)
-                states.append(new_state)
-        with tf.op_scope([initial_state], "sampling"):
-            for i in xrange(len(decoder_inputs)):
-                if i == 0:
-                    sampling_outputs.append(outputs[i])
-                    sampling_states.append(states[i])
-                else:
-                    sampling_output, sampling_state = cell(sampling_outputs[-1], sampling_states[-1])
-                    sampling_outputs.append(sampling_output)
-                    sampling_states.append(sampling_state)
-    return outputs, states, sampling_outputs, sampling_states
-
-
-def rnn_seq2seq(encoder_inputs, decoder_inputs, cell, dtype=tf.float32, scope=None):
-    with tf.variable_scope(scope or "rnn_seq2seq"):
-        _, enc_states = rnn.rnn(cell, encoder_inputs, dtype=dtype)
-        return rnn_decoder(decoder_inputs, enc_states[-1], cell)
+if not (os.path.exists('train.data') and os.path.exists('test.data')):
+    english_data = read_iterator(ENGLISH_CORPUS)
+    french_data = read_iterator(FRENCH_CORPUS)
+    parallel_data = ('%s;;;%s' % (eng, fr) for eng, fr in itertools.izip(english_data, french_data))
+    save_partitions(split_train_test(parallel_data), ['train.data', 'test.data'])
+
+def Xy(data):
+    def split_lines(data):
+        for item in data:
+            yield item.split(';;;')
+    X, y = itertools.tee(split_lines(data))
+    return (item[0] for item in X), (item[1] for item in y)
+
+X_train, y_train = Xy(repeated_read_iterator('train.data'))
+X_test, y_test = Xy(read_iterator('test.data'))
+
+
+# Translation model
 
+MAX_DOCUMENT_LENGTH = 30
+HIDDEN_SIZE = 100
 
 def translate_model(X, y):
     byte_list = skflow.ops.one_hot_matrix(X, 256)
     in_X, in_y, out_y = skflow.ops.seq2seq_inputs(
         byte_list, y, MAX_DOCUMENT_LENGTH, MAX_DOCUMENT_LENGTH)
-    cell = rnn_cell.OutputProjectionWrapper(rnn_cell.GRUCell(HIDDEN_SIZE), 256)
-    decoding, _, sampling_decoding, _ = rnn_seq2seq(in_X, in_y, cell)
+    cell = tf.nn.rnn_cell.OutputProjectionWrapper(tf.nn.rnn_cell.GRUCell(HIDDEN_SIZE), 256)
+    decoding, _, sampling_decoding, _ = skflow.ops.rnn_seq2seq(in_X, in_y, cell)
     return skflow.ops.sequence_classifier(decoding, out_y, sampling_decoding)
 
 
 vocab_processor = skflow.preprocessing.ByteProcessor(
     max_document_length=MAX_DOCUMENT_LENGTH)
 
-x_iter = vocab_processor.transform(X_iter())
-y_iter = vocab_processor.transform(y_iter())
-xpred = np.array(list(vocab_processor.transform(X_pred)))
+x_iter = vocab_processor.transform(X_train)
+y_iter = vocab_processor.transform(y_train)
+xpred = np.array(list(vocab_processor.transform(X_test))[:20])
+ygold = list(y_test)[:20]
 
 PATH = '/tmp/tf_examples/ntm/'
 
 if os.path.exists(PATH):
     translator = skflow.TensorFlowEstimator.restore(PATH)
 else:
     translator = skflow.TensorFlowEstimator(model_fn=translate_model,
-        n_classes=256, continue_training=True)
+        n_classes=256,
+        optimizer='Adam', learning_rate=0.01, batch_size=128,
+        continue_training=True)
 
 while True:
     translator.fit(x_iter, y_iter, logdir=PATH)
@@ -106,7 +121,9 @@ def translate_model(X, y):
     predictions = translator.predict(xpred, axis=2)
     xpred_inp = vocab_processor.reverse(xpred)
     text_outputs = vocab_processor.reverse(predictions)
-    for inp_data, input_text, pred, output_text in zip(xpred, xpred_inp, predictions, text_outputs):
-        print(input_text, output_text)
+    for inp_data, input_text, pred, output_text, gold in zip(xpred, xpred_inp,
+        predictions, text_outputs, ygold):
+        print('English: %s. French (pred): %s, French (gold): %s' %
+            (input_text, output_text, gold.decode('utf-8')))
         print(inp_data, pred)