keras/examples/keras_io/nlp/bidirectional_lstm_imdb.py
2023-06-09 11:49:04 -07:00

63 lines
1.9 KiB
Python

"""
Title: Bidirectional LSTM on IMDB
Author: [fchollet](https://twitter.com/fchollet)
Date created: 2020/05/03
Last modified: 2020/05/03
Description: Train a 2-layer bidirectional LSTM on the IMDB movie review sentiment classification dataset.
Accelerator: GPU
"""
"""
## Setup
"""
import numpy as np
import keras_core as keras
from keras_core import layers
max_features = 20000 # Only consider the top 20k words
maxlen = 200 # Only consider the first 200 words of each movie review
"""
## Build the model
"""
# Input for variable-length sequences of integers
inputs = keras.Input(shape=(None,), dtype="int32")
# Embed each integer in a 128-dimensional vector
x = layers.Embedding(max_features, 128)(inputs)
# Add 2 bidirectional LSTMs
x = layers.Bidirectional(layers.LSTM(64, return_sequences=True))(x)
x = layers.Bidirectional(layers.LSTM(64))(x)
# Add a classifier
outputs = layers.Dense(1, activation="sigmoid")(x)
model = keras.Model(inputs, outputs)
model.summary()
"""
## Load the IMDB movie review sentiment data
"""
(x_train, y_train), (x_val, y_val) = keras.datasets.imdb.load_data(
num_words=max_features
)
print(len(x_train), "Training sequences")
print(len(x_val), "Validation sequences")
# Use pad_sequence to standardize sequence length:
# this will truncate sequences longer than 200 words and zero-pad sequences shorter than 200 words.
x_train = keras.utils.pad_sequences(x_train, maxlen=maxlen)
x_val = keras.utils.pad_sequences(x_val, maxlen=maxlen)
"""
## Train and evaluate the model
You can use the trained model hosted on [Hugging Face Hub](https://huggingface.co/keras-io/bidirectional-lstm-imdb)
and try the demo on [Hugging Face Spaces](https://huggingface.co/spaces/keras-io/bidirectional_lstm_imdb).
"""
model.compile(
optimizer="adam", loss="binary_crossentropy", metrics=["accuracy"]
)
model.fit(
x_train, y_train, batch_size=32, epochs=2, validation_data=(x_val, y_val)
)