add TFXLNetForTokenClassification implementation and unit test

add XLNetForTokenClassification implementation and unit tests

transformers/__init__.py

@@ -83,9 +83,10 @@ if is_torch_available():
                                 CTRLLMHeadModel,
                                 CTRL_PRETRAINED_MODEL_ARCHIVE_MAP)
     from .modeling_xlnet import (XLNetPreTrainedModel, XLNetModel, XLNetLMHeadModel,
-                                XLNetForSequenceClassification, XLNetForMultipleChoice,
-                                XLNetForQuestionAnsweringSimple, XLNetForQuestionAnswering,
-                                load_tf_weights_in_xlnet, XLNET_PRETRAINED_MODEL_ARCHIVE_MAP)
+                                XLNetForSequenceClassification, XLNetForTokenClassification,
+                                XLNetForMultipleChoice, XLNetForQuestionAnsweringSimple,
+                                XLNetForQuestionAnswering, load_tf_weights_in_xlnet,
+                                XLNET_PRETRAINED_MODEL_ARCHIVE_MAP)
     from .modeling_xlm import (XLMPreTrainedModel , XLMModel,
                             XLMWithLMHeadModel, XLMForSequenceClassification,
                             XLMForQuestionAnswering, XLMForQuestionAnsweringSimple,
@@ -136,6 +137,7 @@ if is_tf_available():
     from .modeling_tf_xlnet import (TFXLNetPreTrainedModel, TFXLNetMainLayer,
                                     TFXLNetModel, TFXLNetLMHeadModel,
                                     TFXLNetForSequenceClassification,
+                                    TFXLNetForTokenClassification,
                                     TFXLNetForQuestionAnsweringSimple,
                                     TF_XLNET_PRETRAINED_MODEL_ARCHIVE_MAP)
 

transformers/modeling_tf_xlnet.py

@@ -939,6 +939,59 @@ class TFXLNetForSequenceClassification(TFXLNetPreTrainedModel):
         return outputs  # return logits, (mems), (hidden states), (attentions)
 
 
+@add_start_docstrings("""XLNet Model with a token classification head on top (a linear layer on top of
+    the hidden-states output) e.g. for Named-Entity-Recognition (NER) tasks. """,
+    XLNET_START_DOCSTRING, XLNET_INPUTS_DOCSTRING)
+class TFXLNetForTokenClassification(TFXLNetPreTrainedModel):
+    r"""
+    Outputs: `Tuple` comprising various elements depending on the configuration (config) and inputs:
+        **scores**: ``tf.Tensor`` of shape ``(batch_size, sequence_length, config.num_labels)``
+            Classification scores (before SoftMax).
+        **mems**: (`optional`, returned when ``config.mem_len > 0``)
+            list of ``tf.Tensor`` (one for each layer):
+            that contains pre-computed hidden-states (key and values in the attention blocks) as computed by the model
+            if config.mem_len > 0 else tuple of None. Can be used to speed up sequential decoding and attend to longer context.
+            See details in the docstring of the `mems` input above.
+        **hidden_states**: (`optional`, returned when ``config.output_hidden_states=True``)
+            list of ``tf.Tensor`` (one for the output of each layer + the output of the embeddings)
+            of shape ``(batch_size, sequence_length, hidden_size)``:
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        **attentions**: (`optional`, returned when ``config.output_attentions=True``)
+            list of ``tf.Tensor`` (one for each layer) of shape ``(batch_size, num_heads, sequence_length, sequence_length)``:
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention heads.
+
+    Examples::
+
+        import tensorflow as tf
+        from transformers import XLNetTokenizer, TFXLNetForTokenClassification
+
+        tokenizer = XLNetTokenizer.from_pretrained('xlnet-large-cased')
+        model = TFXLNetForSequenceClassification.from_pretrained('xlnet-large-cased')
+        input_ids = tf.constant(tokenizer.encode("Hello, my dog is cute"))[None, :]  # Batch size 1
+        outputs = model(input_ids)
+        scores = outputs[0]
+
+    """
+    def __init__(self, config, *inputs, **kwargs):
+        super(TFXLNetForTokenClassification, self).__init__(config, *inputs, **kwargs)
+        self.num_labels = config.num_labels
+
+        self.transformer = TFXLNetMainLayer(config, name='transformer')
+        self.classifier = tf.keras.layers.Dense(config.num_labels,
+                                                kernel_initializer=get_initializer(config.initializer_range),
+                                                name='classifier')
+
+    def call(self, inputs, **kwargs):
+        transformer_outputs = self.transformer(inputs, **kwargs)
+        output = transformer_outputs[0]
+
+        logits = self.classifier(output)
+
+        outputs = (logits,) + transformer_outputs[1:]  # Keep mems, hidden states, attentions if there are in it
+
+        return outputs  # return logits, (mems), (hidden states), (attentions)
+
+
 # @add_start_docstrings("""XLNet Model with a span classification head on top for extractive question-answering tasks like SQuAD (a linear layers on top of
 #     the hidden-states output to compute `span start logits` and `span end logits`). """,
 #     XLNET_START_DOCSTRING, XLNET_INPUTS_DOCSTRING)

transformers/modeling_xlnet.py

@@ -1046,6 +1046,106 @@ class XLNetForSequenceClassification(XLNetPreTrainedModel):
 
         return outputs  # return (loss), logits, (mems), (hidden states), (attentions)
 
+@add_start_docstrings("""XLNet Model with a token classification head on top (a linear layer on top of
+                      the hidden-states output) e.g. for Named-Entity-Recognition (NER) tasks. """,
+                      XLNET_START_DOCSTRING,
+                      XLNET_INPUTS_DOCSTRING)
+class XLNetForTokenClassification(XLNetPreTrainedModel):
+    r"""
+    Inputs:
+        **input_ids**: ``torch.LongTensor`` of shape ``(batch_size, num_choices, sequence_length)``:
+            Indices of input sequence tokens in the vocabulary.
+            The second dimension of the input (`num_choices`) indicates the number of choices to scores.
+        **token_type_ids**: (`optional`) ``torch.LongTensor`` of shape ``(batch_size, sequence_length)``:
+            Segment token indices to indicate first and second portions of the inputs.
+            Indices are selected in ``[0, 1]``: ``0`` corresponds to a `sentence A` token, ``1``
+        **attention_mask**: (`optional`) ``torch.FloatTensor`` of shape ``(batch_size, sequence_length)``:
+            Mask to avoid performing attention on padding token indices.
+            Mask values selected in ``[0, 1]``:
+            ``1`` for tokens that are NOT MASKED, ``0`` for MASKED tokens.
+        **head_mask**: (`optional`) ``torch.FloatTensor`` of shape ``(num_heads,)`` or ``(num_layers, num_heads)``:
+            Mask to nullify selected heads of the self-attention modules.
+            Mask values selected in ``[0, 1]``:
+            ``1`` indicates the head is **not masked**, ``0`` indicates the head is **masked**.
+        **inputs_embeds**: (`optional`) ``torch.FloatTensor`` of shape ``(batch_size, sequence_length, embedding_dim)``:
+            Optionally, instead of passing ``input_ids`` you can choose to directly pass an embedded representation.
+            This is useful if you want more control over how to convert `input_ids` indices into associated vectors
+            than the model's internal embedding lookup matrix.
+        **labels**: (`optional`) ``torch.LongTensor`` of shape ``(batch_size,)``:
+            Labels for computing the multiple choice classification loss.
+            Indices should be in ``[0, ..., num_choices]`` where `num_choices` is the size of the second dimension
+            of the input tensors. (see `input_ids` above)
+
+    Outputs: `Tuple` comprising various elements depending on the configuration (config) and inputs:
+        **loss**: (`optional`, returned when ``labels`` is provided) ``torch.FloatTensor`` of shape ``(1,)``:
+            Classification loss.
+        **scores**: ``torch.FloatTensor`` of shape ``(batch_size, sequence_length, config.num_labels)``
+            Classification scores (before SoftMax).
+        **mems**: (`optional`, returned when ``config.mem_len > 0``)
+            list of ``torch.FloatTensor`` (one for each layer):
+            that contains pre-computed hidden-states (key and values in the attention blocks) as computed by the model
+            if config.mem_len > 0 else tuple of None. Can be used to speed up sequential decoding and attend to longer context.
+            See details in the docstring of the `mems` input above.
+        **hidden_states**: (`optional`, returned when ``config.output_hidden_states=True``)
+            list of ``torch.FloatTensor`` (one for the output of each layer + the output of the embeddings)
+            of shape ``(batch_size, sequence_length, hidden_size)``:
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        **attentions**: (`optional`, returned when ``config.output_attentions=True``)
+            list of ``torch.FloatTensor`` (one for each layer) of shape ``(batch_size, num_heads, sequence_length, sequence_length)``:
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention heads.
+
+    Examples::
+
+        tokenizer = XLNetTokenizer.from_pretrained('xlnet-large-cased')
+        model = XLNetForSequenceClassification.from_pretrained('xlnet-large-cased')
+        input_ids = torch.tensor(tokenizer.encode("Hello, my dog is cute")).unsqueeze(0)  # Batch size 1
+        labels = torch.tensor([1] * input_ids.size(1)).unsqueeze(0)  # Batch size 1
+        outputs = model(input_ids, labels=labels)
+        scores = outputs[0]
+
+    """
+    def __init__(self, config):
+        super(XLNetForTokenClassification, self).__init__(config)
+        self.num_labels = config.num_labels
+
+        self.transformer = XLNetModel(config)
+        self.classifier = nn.Linear(config.hidden_size, config.num_labels)
+
+        self.init_weights()
+
+    def forward(self, input_ids=None, attention_mask=None, mems=None, perm_mask=None, target_mapping=None,
+                token_type_ids=None, input_mask=None, head_mask=None, inputs_embeds=None, labels=None):
+
+        outputs = self.transformer(input_ids,
+                            attention_mask=attention_mask,
+                            mems=mems,
+                            perm_mask=perm_mask,
+                            target_mapping=target_mapping,
+                            token_type_ids=token_type_ids,
+                            input_mask=input_mask,
+                            head_mask=head_mask,
+                            inputs_embeds=inputs_embeds)
+
+        sequence_output = outputs[0]
+
+        logits = self.classifier(sequence_output)
+
+        outputs = (logits,) + outputs[1:]  # Keep mems, hidden states, attentions if there are in it
+        if labels is not None:
+            loss_fct = CrossEntropyLoss()
+            # Only keep active parts of the loss
+            if attention_mask is not None:
+                active_loss = attention_mask.view(-1) == 1
+                active_logits = logits.view(-1, self.num_labels)[active_loss]
+                active_labels = labels.view(-1)[active_loss]
+                loss = loss_fct(active_logits, active_labels)
+            else:
+                loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1))
+            outputs = (loss,) + outputs
+
+        return outputs  # return (loss), logits, (mems), (hidden states), (attentions)
+
+
 @add_start_docstrings("""XLNet Model with a multiple choice classification head on top (a linear layer on top of
     the pooled output and a softmax) e.g. for RACE/SWAG tasks. """,
     XLNET_START_DOCSTRING, XLNET_INPUTS_DOCSTRING)

transformers/tests/modeling_tf_xlnet_test.py

@@ -30,6 +30,7 @@ if is_tf_available():
 
     from transformers.modeling_tf_xlnet import (TFXLNetModel, TFXLNetLMHeadModel,
                                                         TFXLNetForSequenceClassification,
+                                                        TFXLNetForTokenClassification,
                                                         TFXLNetForQuestionAnsweringSimple,
                                                         TF_XLNET_PRETRAINED_MODEL_ARCHIVE_MAP)
 else:
@@ -42,6 +43,7 @@ class TFXLNetModelTest(TFCommonTestCases.TFCommonModelTester):
 
     all_model_classes=(TFXLNetModel, TFXLNetLMHeadModel,
                        TFXLNetForSequenceClassification,
+                       TFXLNetForTokenClassification,
                        TFXLNetForQuestionAnsweringSimple) if is_tf_available() else ()
     test_pruning = False
 
@@ -258,6 +260,26 @@ class TFXLNetModelTest(TFCommonTestCases.TFCommonModelTester):
                 list(list(mem.shape) for mem in result["mems_1"]),
                 [[self.seq_length, self.batch_size, self.hidden_size]] * self.num_hidden_layers)
 
+        def create_and_check_xlnet_for_token_classification(self, config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
+                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels):
+            config.num_labels = input_ids_1.shape[1]
+            model = TFXLNetForTokenClassification(config)
+            inputs = {'input_ids': input_ids_1,
+                      'attention_mask': input_mask,
+                      # 'token_type_ids': token_type_ids
+                      }
+            logits, mems_1 = model(inputs)
+            result = {
+                "mems_1": [mem.numpy() for mem in mems_1],
+                "logits": logits.numpy(),
+            }
+            self.parent.assertListEqual(
+                list(result["logits"].shape),
+                [self.batch_size, self.seq_length, config.num_labels])
+            self.parent.assertListEqual(
+                list(list(mem.shape) for mem in result["mems_1"]),
+                [[self.seq_length, self.batch_size, self.hidden_size]] * self.num_hidden_layers)
+
         def prepare_config_and_inputs_for_common(self):
             config_and_inputs = self.prepare_config_and_inputs()
             (config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
@@ -289,6 +311,10 @@ class TFXLNetModelTest(TFCommonTestCases.TFCommonModelTester):
         config_and_inputs = self.model_tester.prepare_config_and_inputs()
         self.model_tester.create_and_check_xlnet_sequence_classif(*config_and_inputs)
 
+    def test_xlnet_token_classification(self):
+        config_and_inputs = self.model_tester.prepare_config_and_inputs()
+        self.model_tester.create_and_check_xlnet_for_token_classification(*config_and_inputs)
+
     def test_xlnet_qa(self):
         self.model_tester.set_seed()
         config_and_inputs = self.model_tester.prepare_config_and_inputs()

transformers/tests/modeling_xlnet_test.py

@@ -28,7 +28,8 @@ from transformers import is_torch_available
 if is_torch_available():
     import torch
 
-    from transformers import (XLNetConfig, XLNetModel, XLNetLMHeadModel, XLNetForSequenceClassification, XLNetForQuestionAnswering)
+    from transformers import (XLNetConfig, XLNetModel, XLNetLMHeadModel, XLNetForSequenceClassification,
+                              XLNetForTokenClassification, XLNetForQuestionAnswering)
     from transformers.modeling_xlnet import XLNET_PRETRAINED_MODEL_ARCHIVE_MAP
 else:
     pytestmark = pytest.mark.skip("Require Torch")
@@ -38,7 +39,7 @@ from .configuration_common_test import ConfigTester
 
 class XLNetModelTest(CommonTestCases.CommonModelTester):
 
-    all_model_classes=(XLNetModel, XLNetLMHeadModel,
+    all_model_classes=(XLNetModel, XLNetLMHeadModel, XLNetForTokenClassification,
                     XLNetForSequenceClassification, XLNetForQuestionAnswering) if is_torch_available() else ()
     test_pruning = False
 
@@ -107,10 +108,12 @@ class XLNetModelTest(CommonTestCases.CommonModelTester):
             sequence_labels = None
             lm_labels = None
             is_impossible_labels = None
+            token_labels = None
             if self.use_labels:
                 lm_labels = ids_tensor([self.batch_size, self.seq_length], self.vocab_size)
                 sequence_labels = ids_tensor([self.batch_size], self.type_sequence_label_size)
                 is_impossible_labels = ids_tensor([self.batch_size], 2).float()
+                token_labels = ids_tensor([self.batch_size, self.seq_length], self.type_vocab_size)
 
             config = XLNetConfig(
                 vocab_size_or_config_json_file=self.vocab_size,
@@ -129,14 +132,14 @@ class XLNetModelTest(CommonTestCases.CommonModelTester):
                 num_labels=self.type_sequence_label_size)
 
             return (config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
-                    target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels)
+                    target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels, token_labels)
 
         def set_seed(self):
             random.seed(self.seed)
             torch.manual_seed(self.seed)
 
         def create_and_check_xlnet_base_model(self, config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
-                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels):
+                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels, token_labels):
             model = XLNetModel(config)
             model.eval()
 
@@ -164,7 +167,7 @@ class XLNetModelTest(CommonTestCases.CommonModelTester):
                 [[self.seq_length, self.batch_size, self.hidden_size]] * self.num_hidden_layers)
 
         def create_and_check_xlnet_lm_head(self, config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
-                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels):
+                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels, token_labels):
             model = XLNetLMHeadModel(config)
             model.eval()
 
@@ -204,7 +207,7 @@ class XLNetModelTest(CommonTestCases.CommonModelTester):
                 [[self.mem_len, self.batch_size, self.hidden_size]] * self.num_hidden_layers)
 
         def create_and_check_xlnet_qa(self, config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
-                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels):
+                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels, token_labels):
             model = XLNetForQuestionAnswering(config)
             model.eval()
 
@@ -261,8 +264,40 @@ class XLNetModelTest(CommonTestCases.CommonModelTester):
                 list(list(mem.size()) for mem in result["mems"]),
                 [[self.seq_length, self.batch_size, self.hidden_size]] * self.num_hidden_layers)
 
+        def create_and_check_xlnet_token_classif(self, config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
+                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels, token_labels):
+            model = XLNetForTokenClassification(config)
+            model.eval()
+
+            logits, mems_1 = model(input_ids_1)
+            loss, logits, mems_1 = model(input_ids_1, labels=token_labels)
+
+            result = {
+                "loss": loss,
+                "mems_1": mems_1,
+                "logits": logits,
+            }
+
+            self.parent.assertListEqual(
+                list(result["loss"].size()),
+                [])
+            self.parent.assertListEqual(
+                list(result["logits"].size()),
+                [self.batch_size, self.seq_length, self.type_sequence_label_size])
+            self.parent.assertListEqual(
+                list(list(mem.size()) for mem in result["mems_1"]),
+                [[self.seq_length, self.batch_size, self.hidden_size]] * self.num_hidden_layers)
+
+        def prepare_config_and_inputs_for_common(self):
+            config_and_inputs = self.prepare_config_and_inputs()
+            (config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
+                target_mapping, segment_ids, lm_labels,
+                sequence_labels, is_impossible_labels) = config_and_inputs
+            inputs_dict = {'input_ids': input_ids_1}
+            return config, inputs_dict
+
         def create_and_check_xlnet_sequence_classif(self, config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
-                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels):
+                target_mapping, segment_ids, lm_labels, sequence_labels, is_impossible_labels, token_labels):
             model = XLNetForSequenceClassification(config)
             model.eval()
 
@@ -289,7 +324,7 @@ class XLNetModelTest(CommonTestCases.CommonModelTester):
             config_and_inputs = self.prepare_config_and_inputs()
             (config, input_ids_1, input_ids_2, input_ids_q, perm_mask, input_mask,
                 target_mapping, segment_ids, lm_labels,
-                sequence_labels, is_impossible_labels) = config_and_inputs
+                sequence_labels, is_impossible_labels, token_labels) = config_and_inputs
             inputs_dict = {'input_ids': input_ids_1}
             return config, inputs_dict
 
@@ -316,6 +351,11 @@ class XLNetModelTest(CommonTestCases.CommonModelTester):
         config_and_inputs = self.model_tester.prepare_config_and_inputs()
         self.model_tester.create_and_check_xlnet_sequence_classif(*config_and_inputs)
 
+    def test_xlnet_token_classif(self):
+        self.model_tester.set_seed()
+        config_and_inputs = self.model_tester.prepare_config_and_inputs()
+        self.model_tester.create_and_check_xlnet_token_classif(*config_and_inputs)
+
     def test_xlnet_qa(self):
         self.model_tester.set_seed()
         config_and_inputs = self.model_tester.prepare_config_and_inputs()