# DataBack: Dataset of SAT Formulas and Backbone Variable Phases

## What is DataBack
`DataBack` is a dataset that consists of 120,286 SAT formulas (in CNF format), each labeled with the phases of its backbone variables. 
`DataBack` contains two distinct subsets: the pre-training set, named `DataBack-PT`, and the fine-tuning set, named `DataBack-FT`, for pre-training and fine-tuning our `NeuroBack` model, respectively. To learn more about `NeuroBack` and `DataBack`, please refer to our [`NeuroBack paper`](https://arxiv.org/pdf/2110.14053.pdf). 

The state-of-the-art backbone extractor, [`CadiBack`](https://github.com/arminbiere/cadiback), has been employed to extract the backbone variable phases. To learn more about `CadiBack`, please refer to the [`CadiBack paper`](https://wenxiwang.github.io/papers/cadiback.pdf).


## Directory Structure
```
|- original             # Original CNF formulas and their backbone variable phases
|    |- cnf_pt.tar.gz   # CNF formulas for pre-training
|    |- bb_pt.tar.gz    # Backbone phases for pre-training formulas
|    |- cnf_ft.tar.gz   # CNF formulas for fine-tuning
|    |- bb_ft.tar.gz    # Backbone phases for fine-tuning formulas
|
|- dual                   # Dual CNF formulas and their backbone variable phases
|    |- d_cnf_pt.tar.gz   # Dual CNF formulas for pre-training
|    |- d_bb_pt.tar.gz    # Backbone phases for dual pre-training formulas
|    |- d_cnf_ft.tar.gz   # Dual CNF formulas for fine-tuning
|    |- d_bb_ft.tar.gz    # Backbone phases for dual fine-tuning formulas
```

## File Naming Convention
In the original directory, each CNF tar file (**`cnf_*.tar.gz`**) contains compressed CNF files named: **`[cnf_name].[compression_format]`**, where **`[compression_format]`** could be bz2, lzma, xz, gz, etc. Correspondingly, each backbone tar file (**`bb_*.tar.gz`**) comprises compressed backbone files named: **`[cnf_name].backbone.xz`**. It is important to note that a compressed CNF file will always share its **`[cnf_name]`** with its associated compressed backbone file.

For dual formulas and their corresponding backbone files, the naming convention remains consistent, but with an added **`d_`** prefix.

## Format of the Extracted Backbone File 
The extracted backbone file (`*.backbone`) adheres to the output format of [`CadiBack`](https://github.com/arminbiere/cadiback). 

## References
If you use `DataBack` in your research, please kindly cite the following papers.

[`NeuroBack paper`](https://arxiv.org/pdf/2110.14053.pdf):
```bib
@article{wang2023neuroback,
  author = {Wang, Wenxi and
            Hu, Yang and
            Tiwari, Mohit and
            Khurshid, Sarfraz and
            McMillan, Kenneth L. and
            Miikkulainen, Risto},
  title = {NeuroBack: Improving CDCL SAT Solving using Graph Neural Networks},
  journal={arXiv preprint arXiv:2110.14053},
  year={2021}
}
```

[`CadiBack paper`](https://wenxiwang.github.io/papers/cadiback.pdf):
```bib
@inproceedings{biere2023cadiback,
  title={CadiBack: Extracting Backbones with CaDiCaL},
  author={Biere, Armin and Froleyks, Nils and Wang, Wenxi},
  booktitle={26th International Conference on Theory and Applications of Satisfiability Testing (SAT 2023)},
  year={2023},
  organization={Schloss Dagstuhl-Leibniz-Zentrum f{\"u}r Informatik}
}
```
## Contributors
Wenxi Wang (wenxiw@utexas.edu), Yang Hu (huyang@utexas.edu)