adabound 0.0.5
AdaBound optimization algorithm, build on PyTorch.
License: Apache
Requires Python: >=3.6.0
Keywords: machine learning,deep learning

# AdaBound
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An optimizer that trains as fast as Adam and as good as SGD, for developing state-of-the-art 
deep learning models on a wide variety of pupolar tasks in the field of CV, NLP, and etc.

Based on Luo et al. (2019). 
[Adaptive Gradient Methods with Dynamic Bound of Learning Rate](https://openreview.net/forum?id=Bkg3g2R9FX).
In *Proc. of ICLR 2019*.

<p align='center'>
  <img src='https://www.luolc.com/assets/research/adabound/adabound-banner.png' width="60%"/>
</p>

## Quick Links

- [Website](https://www.luolc.com/publications/adabound/)
- [Demos](./demos)

## Installation

AdaBound requires Python 3.6.0 or later.
We currently provide PyTorch version and AdaBound for TensorFlow is coming soon.

### Installing via pip

The preferred way to install AdaBound is via `pip` with a virtual environment.
Just run 
```bash
pip install adabound
```
in your Python environment and you are ready to go!

### Using source code

As AdaBound is a Python class with only 100+ lines, an alternative way is directly downloading
[adabound.py](./adabound/adabound.py) and copying it to your project.

## Usage

You can use AdaBound just like any other PyTorch optimizers.

```python3
optimizer = adabound.AdaBound(model.parameters(), lr=1e-3, final_lr=0.1)
```

As described in the paper, AdaBound is an optimizer that behaves like Adam at the beginning of
training, and gradually transforms to SGD at the end.
The `final_lr` parameter indicates AdaBound would transforms to an SGD with this learning rate.
In common cases, a default final learning rate of `0.1` can achieve relatively good and stable
results on unseen data.
It is not very sensitive to its hyperparameters.
See Appendix G of the paper for more details.

Despite of its robust performance, we still have to state that, **there is no silver bullet**.
It does not mean that you will be free from tuning hyperparameters once using AdaBound.
The performance of a model depends on so many things including the task, the model structure,
the distribution of data, and etc.
**You still need to decide what hyperparameters to use based on your specific situation,
but you may probably use much less time than before!**

## Demos

Thanks to the awesome work by the GitHub team and the Jupyter team, the Jupyter notebook (`.ipynb`)
files can render directly on GitHub.
We provide several notebooks (like [this one](./demos/cifar10/visualization.ipynb)) for better
visualization.
We hope to illustrate the robust performance of AdaBound through these examples.

For the full list of demos, please refer to [this page](./demos).

## Citing
If you use AdaBound in your research, please cite [Adaptive Gradient Methods with Dynamic Bound of Learning Rate](https://openreview.net/forum?id=Bkg3g2R9FX).
```text
@inproceedings{Luo2019AdaBound,
  author = {Luo, Liangchen and Xiong, Yuanhao and Liu, Yan and Sun, Xu},
  title = {Adaptive Gradient Methods with Dynamic Bound of Learning Rate},
  booktitle = {Proceedings of the 7th International Conference on Learning Representations},
  month = {May},
  year = {2019},
  address = {New Orleans, Louisiana}
}
```

## License
[Apache 2.0](./LICENSE)