# Text Embedding with Transformers

*author: [Jael Gu](https://github.com/jaelgu)*

<br />

## Description

A text embedding operator takes a sentence, paragraph, or document in string as an input
and output an embedding vector in ndarray which captures the input's core semantic elements.
This operator is implemented with pre-trained models from [Huggingface Transformers](https://huggingface.co/docs/transformers).

<br />

## Code Example

Use the pre-trained model 'distilbert-base-cased'
to generate a text embedding for the sentence "Hello, world.".

*Write the pipeline*:

```python
import towhee

(
    towhee.dc(["Hello, world."])
          .text_embedding.transformers(model_name="distilbert-base-cased")
)
```

*Write a same pipeline with explicit inputs/outputs name specifications:*

```python
import towhee

(
    towhee.dc['text'](["Hello, world."])
          .text_embedding.transformers['text', 'vec'](model_name="distilbert-base-cased")
          .show()
)
```

<img src="./result.png" width="800px"/>

<br />

## Factory Constructor

Create the operator via the following factory method:

***text_embedding.transformers(model_name="bert-base-uncased")***

**Parameters:**

***model_name***: *str*

The model name in string.
The default model name is "bert-base-uncased".

Supported model names:

<details><summary>Albert</summary>

  - albert-base-v1
  - albert-large-v1
  - albert-xlarge-v1
  - albert-xxlarge-v1
  - albert-base-v2
  - albert-large-v2
  - albert-xlarge-v2
  - albert-xxlarge-v2
</details>

<details><summary>Bart</summary>

  - facebook/bart-large
</details>

<details><summary>Bert</summary>

  - bert-base-cased
  - bert-large-cased
  - bert-large-uncased
  - bert-base-multilingual-uncased
  - bert-base-multilingual-cased
  - bert-base-chinese
  - bert-base-german-cased
  - bert-large-uncased-whole-word-masking
  - bert-large-cased-whole-word-masking
  - bert-large-uncased-whole-word-masking-finetuned-squad
  - bert-large-cased-whole-word-masking-finetuned-squad
  - bert-base-cased-finetuned-mrpc
  - bert-base-german-dbmdz-cased
  - bert-base-german-dbmdz-uncased
  - cl-tohoku/bert-base-japanese-whole-word-masking
  - cl-tohoku/bert-base-japanese-char
  - cl-tohoku/bert-base-japanese-char-whole-word-masking
  - TurkuNLP/bert-base-finnish-cased-v1
  - TurkuNLP/bert-base-finnish-uncased-v1
  - wietsedv/bert-base-dutch-cased
</details>

<details><summary>BertGeneration</summary>

  - google/bert_for_seq_generation_L-24_bbc_encoder
</details>

<details><summary>BigBird</summary>

  - google/bigbird-roberta-base
  - google/bigbird-roberta-large
  - google/bigbird-base-trivia-itc
</details>

<details><summary>BigBirdPegasus</summary>

  - google/bigbird-pegasus-large-arxiv
  - google/bigbird-pegasus-large-pubmed
  - google/bigbird-pegasus-large-bigpatent
</details>

<details><summary>CamemBert</summary>

  - camembert-base
  - Musixmatch/umberto-commoncrawl-cased-v1
  - Musixmatch/umberto-wikipedia-uncased-v1
</details>

<details><summary>Canine</summary>

  - google/canine-s
  - google/canine-c
</details>

<details><summary>Convbert</summary>

  - YituTech/conv-bert-base
  - YituTech/conv-bert-medium-small
  - YituTech/conv-bert-small
</details>

<details><summary>CTRL</summary>
  - ctrl
</details>

<details><summary>DeBERTa</summary>

  - microsoft/deberta-base
  - microsoft/deberta-large
  - microsoft/deberta-xlarge
  - microsoft/deberta-base-mnli
  - microsoft/deberta-large-mnli
  - microsoft/deberta-xlarge-mnli
  - microsoft/deberta-v2-xlarge
  - microsoft/deberta-v2-xxlarge
  - microsoft/deberta-v2-xlarge-mnli
  - microsoft/deberta-v2-xxlarge-mnli
</details>

<details><summary>DistilBert</summary>

  - distilbert-base-uncased
  - distilbert-base-uncased-distilled-squad
  - distilbert-base-cased
  - distilbert-base-cased-distilled-squad
  - distilbert-base-german-cased
  - distilbert-base-multilingual-cased
  - distilbert-base-uncased-finetuned-sst-2-english
</details>

<details><summary>Electral</summary>

  - google/electra-small-generator
  - google/electra-base-generator
  - google/electra-large-generator
  - google/electra-small-discriminator
  - google/electra-base-discriminator
  - google/electra-large-discriminator
</details>

<details><summary>Flaubert</summary>

  - flaubert/flaubert_small_cased
  - flaubert/flaubert_base_uncased
  - flaubert/flaubert_base_cased
  - flaubert/flaubert_large_cased
</details>

<details><summary>FNet</summary>

  - google/fnet-base
  - google/fnet-large
</details>

<details><summary>FSMT</summary>

  - facebook/wmt19-ru-en
</details>

<details><summary>Funnel</summary>

  - funnel-transformer/small
  - funnel-transformer/small-base
  - funnel-transformer/medium
  - funnel-transformer/medium-base
  - funnel-transformer/intermediate
  - funnel-transformer/intermediate-base
  - funnel-transformer/large
  - funnel-transformer/large-base
  - funnel-transformer/xlarge-base
  - funnel-transformer/xlarge
</details>

<details><summary>GPT</summary>

  - openai-gpt
  - gpt2
  - gpt2-medium
  - gpt2-large
  - gpt2-xl
  - distilgpt2
  - EleutherAI/gpt-neo-1.3B
  - EleutherAI/gpt-j-6B
</details>

<details><summary>I-Bert</summary>

  - kssteven/ibert-roberta-base
</details>

<details><summary>LED</summary>

  - allenai/led-base-16384
</details>

<details><summary>MobileBert</summary>

  - google/mobilebert-uncased
</details>

<details><summary>MPNet</summary>

  - microsoft/mpnet-base
</details>

<details><summary>Nystromformer</summary>

  - uw-madison/nystromformer-512
</details>

<details><summary>Reformer</summary>

  - google/reformer-crime-and-punishment
</details>

<details><summary>Splinter</summary>

  - tau/splinter-base
  - tau/splinter-base-qass
  - tau/splinter-large
  - tau/splinter-large-qass
</details>

<details><summary>SqueezeBert</summary>

  - squeezebert/squeezebert-uncased
  - squeezebert/squeezebert-mnli
  - squeezebert/squeezebert-mnli-headless
</details>    

<details><summary>TransfoXL</summary>

  - transfo-xl-wt103
</details>

<details><summary>XLM</summary>

  - xlm-mlm-en-2048
  - xlm-mlm-ende-1024
  - xlm-mlm-enfr-1024
  - xlm-mlm-enro-1024
  - xlm-mlm-tlm-xnli15-1024
  - xlm-mlm-xnli15-1024
  - xlm-clm-enfr-1024
  - xlm-clm-ende-1024
  - xlm-mlm-17-1280
  - xlm-mlm-100-1280
</details>

<details><summary>XLMRoberta</summary>

  - xlm-roberta-base
  - xlm-roberta-large
  - xlm-roberta-large-finetuned-conll02-dutch
  - xlm-roberta-large-finetuned-conll02-spanish
  - xlm-roberta-large-finetuned-conll03-english
  - xlm-roberta-large-finetuned-conll03-german
</details>

<details><summary>XLNet</summary>

  - xlnet-base-cased
  - xlnet-large-cased
</details>

<details><summary>Yoso</summary>

  - uw-madison/yoso-4096
</details>

<br />

## Interface

The operator takes a piece of text in string as input.
It loads tokenizer and pre-trained model using model name.
and then return text embedding in ndarray.

***__call__(txt)***

**Parameters:**

***txt***: *str*

​	The text in string.


**Returns**:

*numpy.ndarray*

​	The text embedding extracted by model.


***save_model(format='pytorch', path='default')***

Save model to local with specified format.

**Parameters:**

***format***: *str*

​	The format of saved model, defaults to 'pytorch'.

***format***: *path*

​	The path where model is saved to. By default, it will save model to the operator directory.


***supported_model_names(format=None)***

Get a list of all supported model names or supported model names for specified model format.

**Parameters:**

***format***: *str*

​	The model format such as 'pytorch', 'torchscript'.