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This featurizer is a dense featurizer. If you're interested in learning how these work you might appreciate readingthe original article. Recognition should be given to Benjamin Heinzerling and Michael Strube for making these available.

A main feature of these types of embeddings is that they are relatively lightweight but also that they're availability in many languages. BytePair embeddings exist for 277 languages that are pretrained on wikipedia.

More information on these embeddings can be found here. When you scroll down you will notice a large of languages that are available. Here's some examples from that list that give a detailed view of available vectors:

Configurable Variables

  • lang: specifies the lanuage that you'll use, default = "en"
  • dim: specifies the dimension of the subword embeddings, default = 25,
  • vs: specifies the vocabulary size of the segmentation model, default = 1000,
  • vs_fallback: if set to True and the given vocabulary size can't be loaded for the given model, the closest size is chosen, default=True

Base Usage

The configuration file below demonstrates how you might use the BytePair embeddings. The component will automatically download the required embeddings and save them in ~/.cache. Both the embeddings as well as a model file will be saved.

language: en

- name: WhitespaceTokenizer
- name: LexicalSyntacticFeaturizer
- name: CountVectorsFeaturizer
  analyzer: char_wb
  min_ngram: 1
  max_ngram: 4
- name: rasa_nlu_examples.featurizers.dense.BytePairFeaturizer
  lang: en
  vs: 1000
  dim: 25
- name: DIETClassifier
  epochs: 100