Module rust_bert::models::prophetnet

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ProphetNet (ProphetNet: Predicting Future N-gram for Sequence-to-Sequence Pre-training)

Implementation of the ProphetNet language model (ProphetNet: Predicting Future N-gram for Sequence-to-Sequence Pre-training Qi, Yan, Gong, Liu, Duan, Chen, Zhang, Zhou, 2020). The base model is implemented in the prophetnet_model::ProphetNetModel struct. Two language model heads have also been implemented:

  • Conditional language generation (encoder-decoder architecture): prophetnet_model::ProphetNetForConditionalGeneration implementing the common generation_utils::LanguageGenerator trait shared between the models used for generation (see pipelines for more information)
  • Causal language generation (decoder architecture): prophetnet_model::ProphetNetForCausalGeneration

Model set-up and pre-trained weights loading

A full working example (summarization) is provided in examples/summarization_prophetnet, run with cargo run --example summarization_prophetnet. 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.
  • ProphetNetTokenizer using a vocab.txt vocabulary
use rust_bert::pipelines::common::ModelType;
use rust_bert::pipelines::summarization::{SummarizationConfig, SummarizationModel};
use rust_bert::prophetnet::{
    ProphetNetConfigResources, ProphetNetModelResources, ProphetNetVocabResources,
};
use rust_bert::resources::RemoteResource;
use tch::Device;

fn main() -> anyhow::Result<()> {
    use rust_bert::pipelines::common::ModelResource;
    let config_resource = Box::new(RemoteResource::from_pretrained(
        ProphetNetConfigResources::PROPHETNET_LARGE_CNN_DM,
    ));
    let vocab_resource = Box::new(RemoteResource::from_pretrained(
        ProphetNetVocabResources::PROPHETNET_LARGE_CNN_DM,
    ));
    let weights_resource = Box::new(RemoteResource::from_pretrained(
        ProphetNetModelResources::PROPHETNET_LARGE_CNN_DM,
    ));

    let summarization_config = SummarizationConfig {
        model_type: ModelType::ProphetNet,
        model_resource: ModelResource::Torch(weights_resource),
        config_resource,
        vocab_resource,
        merges_resource: None,
        length_penalty: 1.2,
        num_beams: 4,
        no_repeat_ngram_size: 3,
        device: Device::cuda_if_available(),
        ..Default::default()
    };
    let summarization_model = SummarizationModel::new(summarization_config)?;

    let input = ["In findings published Tuesday in Cornell University's arXiv by a team of scientists \
from the University of Montreal and a separate report published Wednesday in Nature Astronomy by a team \
from University College London (UCL), the presence of water vapour was confirmed in the atmosphere of K2-18b, \
a planet circling a star in the constellation Leo. This is the first such discovery in a planet in its star's \
habitable zone — not too hot and not too cold for liquid water to exist. The Montreal team, led by Björn Benneke, \
used data from the NASA's Hubble telescope to assess changes in the light coming from K2-18b's star as the planet \
passed between it and Earth. They found that certain wavelengths of light, which are usually absorbed by water, \
weakened when the planet was in the way, indicating not only does K2-18b have an atmosphere, but the atmosphere \
contains water in vapour form. The team from UCL then analyzed the Montreal team's data using their own software \
and confirmed their conclusion. This was not the first time scientists have found signs of water on an exoplanet, \
but previous discoveries were made on planets with high temperatures or other pronounced differences from Earth. \
\"This is the first potentially habitable planet where the temperature is right and where we now know there is water,\" \
said UCL astronomer Angelos Tsiaras. \"It's the best candidate for habitability right now.\" \"It's a good sign\", \
said Ryan Cloutier of the Harvard–Smithsonian Center for Astrophysics, who was not one of either study's authors. \
\"Overall,\" he continued, \"the presence of water in its atmosphere certainly improves the prospect of K2-18b being \
a potentially habitable planet, but further observations will be required to say for sure. \" \
K2-18b was first identified in 2015 by the Kepler space telescope. It is about 110 light-years from Earth and larger \
but less dense. Its star, a red dwarf, is cooler than the Sun, but the planet's orbit is much closer, such that a year \
on K2-18b lasts 33 Earth days. According to The Guardian, astronomers were optimistic that NASA's James Webb space \
telescope — scheduled for launch in 2021 — and the European Space Agency's 2028 ARIEL program, could reveal more \
about exoplanets like K2-18b."];

    //    Credits: WikiNews, CC BY 2.5 license (https://en.wikinews.org/wiki/Astronomers_find_water_vapour_in_atmosphere_of_exoplanet_K2-18b)
    let _output = summarization_model.summarize(&input)?;
    for sentence in _output {
        println!("{}", sentence);
    }

    Ok(())
}

Structs