This model provides a GPT-2 language model trained with SimCTG on the English Wikipedia based on our paper [_A Contrastive Framework for Neural Text Generation_](https://arxiv.org/abs/2202.06417).

We provide a detailed tutorial on how to apply SimCTG and Contrastive Search in our [project repo](https://github.com/yxuansu/SimCTG#4-huggingface-style-tutorials-back-to-top). In the following, we illustrate a brief tutorial on how to use our approach to perform text generation.

## 1. Installation of SimCTG:
```yaml
pip install simctg --upgrade
```

## 2. Initialize SimCTG Model:
```python
import torch
# load SimCTG language model
from simctg.simctggpt import SimCTGGPT
model_name = r'cambridgeltl/simctg_english_wikipedia'
model = SimCTGGPT(model_name)
model.eval()
tokenizer = model.tokenizer
```

## 3. Prepare the Text Prefix:
```python
prefix_text = r"Insect farming is the practice of raising and breeding insects as livestock, also referred to as minilivestock or micro stock. Insects may be farmed for the commodities"
print ('Prefix is: {}'.format(prefix_text))
tokens = tokenizer.tokenize(prefix_text)
input_ids = tokenizer.convert_tokens_to_ids(tokens)
input_ids = torch.LongTensor(input_ids).view(1,-1)
```

## 4. Generate Text with Contrastive Search:
```python
beam_width, alpha, decoding_len = 5, 0.6, 128
output = model.fast_contrastive_search(input_ids=input_ids, beam_width=beam_width, 
                                       alpha=alpha, decoding_len=decoding_len) 
print("Output:\n" + 100 * '-')
print(tokenizer.decode(output))
'''
  Prefix is: Insect farming is the practice of raising and breeding insects as livestock, also referred to as minilivestock or 
             micro stock. Insects may be farmed for the commodities
  Output:
  ----------------------------------------------------------------------------------------------------
  Insect farming is the practice of raising and breeding insects as livestock, also referred to as minilivestock or micro stock. 
  Insects may be farmed for the commodities they produce, such as honey, corn, sorghum, and other crops. In some cases, the 
  production of insects is a way to increase income for the owner or his family. This type of farming has been described as "an 
  economic system that benefits all people regardless of race, sex, or social status" (p. 9). A large number of farmers in North 
  America, Europe, and South America have used the method of farming for food production in order to feed their families and livestock. 
  The most common method of farming is by hand-cropping, which consists of cutting a hole in the ground and using a saw
'''
```

For more details of our work, please refer to our main [project repo](https://github.com/yxuansu/SimCTG).

## 5. Citation:
If you find our paper and resources useful, please kindly leave a star and cite our paper. Thanks!

```bibtex
@article{su2022contrastive,
  title={A Contrastive Framework for Neural Text Generation},
  author={Su, Yixuan and Lan, Tian and Wang, Yan and Yogatama, Dani and Kong, Lingpeng and Collier, Nigel},
  journal={arXiv preprint arXiv:2202.06417},
  year={2022}
}
```