Module rust_bert::models::mbart

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MBart (Liu et al.)

Implementation of the MBart language model (Multilingual Denoising Pre-training for Neural Machine Translation Liu, Gu, Goyal, Li, Edunov, Ghazvininejad, Lewis, Zettlemoyer, 2020). The base model is implemented in the mbart_model::MBartModel struct. The model also includes a language model head: mbart_model::MBartForConditionalGeneration implementing the common generation_utils::LanguageGenerator trait shared between the models used for generation (see pipelines for more information).

Model set-up and pre-trained weights loading

The translation capabilities are illustrated in examples/translation_mbart, run with cargo run --example translation_mbart. All models expect the following resources:

  • Configuration file expected to have a structure following the Transformers library
  • Model weights are expected to have a structure and parameter names following the Transformers library. A conversion using the Python utility scripts is required to convert the .bin weights to the .ot format.
  • MBart50Tokenizer using a spiece.model SentencePiece model Pretrained models are available and can be downloaded using RemoteResources.
use tch::{nn, Device};
use rust_bert::mbart::{MBartConfig, MBartModel};
use rust_bert::resources::{LocalResource, ResourceProvider};
use rust_bert::Config;
use rust_tokenizers::tokenizer::MBart50Tokenizer;

let config_resource = LocalResource {
    local_path: PathBuf::from("path/to/config.json"),
};
let vocab_resource = LocalResource {
    local_path: PathBuf::from("path/to/vocab.txt"),
};
let weights_resource = LocalResource {
    local_path: PathBuf::from("path/to/model.ot"),
};
let config_path = config_resource.get_local_path()?;
let vocab_path = vocab_resource.get_local_path()?;
let weights_path = weights_resource.get_local_path()?;

let device = Device::cuda_if_available();
let mut vs = nn::VarStore::new(device);
let tokenizer: MBart50Tokenizer =
    MBart50Tokenizer::from_file(vocab_path.to_str().unwrap(), false)?;
let config = MBartConfig::from_file(config_path);
let mbart_model = MBartModel::new(&vs.root(), &config);
vs.load(weights_path)?;

Structs

Type Aliases