PAU - Padé Activation Units

Padé Activation Units: End-to-end Learning of Activation Functions in Deep Neural Network

Arxiv link: https://arxiv.org/abs/1907.06732

1. About Padé Activation Units

Padé Activation Units (PAU) are a novel learnable activation function. PAUs encode activation functions as rational functions, trainable in an end-to-end fashion using backpropagation and can be seemingless integrated into any neural network in the same way as common activation functions (e.g. ReLU).

PAU matches or outperforms common activations in terms of predictive performance and training time. And, therefore relieves the network designer of having to commit to a potentially underperforming choice.

2. Dependencies

PyTorch>=1.1.0
CUDA>=10.1

3. Installation

PAU is implemented as a pytorch extension using CUDA 10.2. So all that is needed is to install the extension.

pip3 install --upgrade pip
pip3 install pau

If installation does not work, please run:

pip3 install wheel

For CUDA 10.1, download the wheel corresponding to your python3 version in the wheelhouse repo and install it with:

pip3 install pau-0.0.16-101-cp{your_version}-manylinux2014_x86_64.whl

If you encounter any trouble installing pau, please contact this person.

4. Using PAU in Neural Networks

PAU can be integrated in the same way as any other common activation function.

import torch
from pau_torch import PAU

model = torch.nn.Sequential(
    torch.nn.Linear(D_in, H),
    PAU(), # e.g. instead of torch.nn.ReLU()
    torch.nn.Linear(H, D_out),
)

5. Reproducing Results

To reproduce the reported results of the paper execute:

$ export PYTHONPATH="./" $ python experiments/main.py --dataset mnist --arch conv --optimizer adam --lr 2e-3

# DATASET: Name of the dataset, for MNIST use mnist and for Fashion-MNIST use fmnist
# ARCH: selected neural network architecture: vgg, lenet or conv
# OPTIMIZER: either adam or sgd
# LR: learning rate