pimdh / svae-temp

Hyperspherical Variational Auto-Encoders

Tensorflow implementation of Hyperspherical Variational Auto-Encoders

Overview

This library contains a Tensorflow implementation of the hyperspherical variational auto-encoder, or S-VAE, as presented in [1](link to our paper).

Dependencies

• python>=3.6
• tensorflow>=1.7.0: http://tensorflow.org
• scipy: https://scipy.org

Installation

To install, run

$ python setup.py install

Structure

• distributions: Tensorflow implementation of the von Mises-Fisher and hyperspherical Uniform distributions. Both inherit from tf.distributions.Distribution
• ops: Low-level operations used for computing the exponentially scaled modified Bessel function of the first kind and its derivative.
• examples: Example code for using the library within a Tensorflow project

Usage

Please have a look into the examples folder. We adapted our implementation to follow the structure of the recently proposed Tensorflow Distribution library, (Dillon et al, 2017).

Please cite [1] in your work when using this library in your experiments.

Sampling von Mises-Fisher

To sample the von Mises-Fisher distribution we follow the rejection sampling procedure as outlined by Ulrich, 1984. This simulation pipeline is visualized below:

Note that as is a scalar, this approach does not suffer from the curse of dimensionality. For the final transformation, , a Householder reflection is utilized.

Feedback

For questions and comments, feel free to contact Nicola De Cao.

License

MIT

Citation

[1] Davidson, T. R., Falorsi, L., De Cao, N., Kipf, T.,
and Tomczak, J. M. (2018). Hyperspherical Variational
Auto-Encoders. arXiv.

BibTeX format:

@article{s-vae18,
  title={{Hyperspherical Variational Auto-Encoders}},
  author={Davidson, Tim R. and
          Falorsi, Luca and
          De Cao, Nicola and
          Thomas, Kipf and
          Tomczak, Jakub M.},
  journal={arXiv preprint arXiv:},
  year={2018}
}