# MaskGAN: Better Text Generation via Filling in the ______

Code for [*MaskGAN: Better Text Generation via Filling in the
______*](https://arxiv.org/abs/1801.07736) published at ICLR 2018.

## Requirements

*   TensorFlow >= v1.3

## Instructions

Warning: The open-source version of this code is still in the process of being
tested. Pretraining may not work correctly.

For training on PTB:

1. (Optional) Pretrain a LM on PTB and store the checkpoint in /tmp/pretrain-lm/.
Instructions WIP.

2. (Optional) Run MaskGAN in MLE pretraining mode:

```bash
python train_mask_gan.py \
 --data_dir='/tmp/ptb' \
 --batch_size=20 \
 --sequence_length=20 \
 --base_directory='/tmp/maskGAN' \
 --hparams="gen_rnn_size=650,dis_rnn_size=650,gen_num_layers=2,dis_num_layers=2,gen_learning_rate=0.00074876,dis_learning_rate=5e-4,baseline_decay=0.99,dis_train_iterations=1,gen_learning_rate_decay=0.95" \
 --mode='TRAIN' \
 --max_steps=100000 \
 --language_model_ckpt_dir=/tmp/pretrain-lm/ \
 --generator_model='seq2seq_vd' \
 --discriminator_model='rnn_zaremba' \
 --is_present_rate=0.5 \
 --summaries_every=10 \
 --print_every=250 \
 --max_num_to_print=3 \
 --gen_training_strategy=cross_entropy \
 --seq2seq_share_embedding
```

3. Run MaskGAN in GAN mode:
```bash
python train_mask_gan.py \
 --data_dir='/tmp/ptb' \
 --batch_size=128 \
 --sequence_length=20 \
 --base_directory='/tmp/maskGAN' \
 --mask_strategy=contiguous \
 --maskgan_ckpt='/tmp/maskGAN' \
 --hparams="gen_rnn_size=650,dis_rnn_size=650,gen_num_layers=2,dis_num_layers=2,gen_learning_rate=0.000038877,gen_learning_rate_decay=1.0,gen_full_learning_rate_steps=2000000,gen_vd_keep_prob=0.33971,rl_discount_rate=0.89072,dis_learning_rate=5e-4,baseline_decay=0.99,dis_train_iterations=2,dis_pretrain_learning_rate=0.005,critic_learning_rate=5.1761e-7,dis_vd_keep_prob=0.71940" \
 --mode='TRAIN' \
 --max_steps=100000 \
 --generator_model='seq2seq_vd' \
 --discriminator_model='seq2seq_vd' \
 --is_present_rate=0.5 \
 --summaries_every=250 \
 --print_every=250 \
 --max_num_to_print=3 \
 --gen_training_strategy='reinforce' \
 --seq2seq_share_embedding=true \
 --baseline_method=critic \
 --attention_option=luong
```

4. Generate samples:
```bash
python generate_samples.py \
 --data_dir /tmp/ptb/ \
 --data_set=ptb \
 --batch_size=256 \
 --sequence_length=20 \
 --base_directory /tmp/imdbsample/ \
 --hparams="gen_rnn_size=650,dis_rnn_size=650,gen_num_layers=2,gen_vd_keep_prob=0.33971" \
 --generator_model=seq2seq_vd \
 --discriminator_model=seq2seq_vd \
 --is_present_rate=0.0 \
 --maskgan_ckpt=/tmp/maskGAN \
 --seq2seq_share_embedding=True \
 --dis_share_embedding=True \
 --attention_option=luong \
 --mask_strategy=contiguous \
 --baseline_method=critic \
 --number_epochs=4
```

## Contact for Issues

*   Liam Fedus, @liamb315 <liam.fedus@gmail.com>
*   Andrew M. Dai, @a-dai <adai@google.com>