Files
keras-language-modeling/answer_to_question.py
T

131 lines
4.3 KiB
Python

from __future__ import print_function
import numpy as np
import os
from keras.engine import Input
from keras.layers import LSTM, RepeatVector, TimeDistributed, Dense, Activation
from keras.models import Model
# can remove this depending on ide...
os.environ['INSURANCE_QA'] = '/media/moloch/HHD/MachineLearning/data/insuranceQA/pyenc'
import sys
try:
import cPickle as pickle
except:
import pickle
class InsuranceQA:
def __init__(self):
try:
data_path = os.environ['INSURANCE_QA']
except KeyError:
print("INSURANCE_QA is not set. Set it to your clone of https://github.com/codekansas/insurance_qa_python")
sys.exit(1)
self.path = data_path
self.vocab = self.load('vocabulary')
self.table = InsuranceQA.VocabularyTable(self.vocab.values())
def load(self, name):
return pickle.load(open(os.path.join(self.path, name), 'rb'))
class VocabularyTable:
''' Identical to CharacterTable from Keras example '''
def __init__(self, words):
self.words = sorted(set(words))
self.words_indices = dict((c, i) for i, c in enumerate(self.words))
self.indices_words = dict((i, c) for i, c in enumerate(self.words))
def encode(self, sentence, maxlen):
indices = np.zeros((maxlen, len(self.words)))
for i, w in enumerate(sentence):
if i == maxlen: break
indices[i, self.words_indices[w]] = 1
return indices
def decode(self, indices, calc_argmax=True):
if calc_argmax:
indices = indices.argmax(axis=-1)
return ' '.join(self.indices_words[x] for x in indices)
def get_model(question_maxlen, answer_maxlen, vocab_len, n_hidden):
answer = Input(shape=(answer_maxlen, vocab_len))
# answer = Masking(mask_value=0.)(answer)
# encoder rnn
encode_rnn = LSTM(n_hidden, return_sequences=False)(answer)
# can add more layers
for i in range(2):
encode_rnn = LSTM(n_hidden, return_sequences=True)(encode_rnn)
# repeat it maxlen times
repeat_encoding = RepeatVector(question_maxlen)(encode_rnn)
# decoder rnn
decode_rnn = LSTM(n_hidden, return_sequences=True)(repeat_encoding)
# can add more layers
for i in range(2):
decode_rnn = LSTM(n_hidden, return_sequences=True)(decode_rnn)
# output
dense = TimeDistributed(Dense(vocab_len))(decode_rnn)
softmax = Activation('softmax')(dense)
# compile the model
model = Model([answer], [softmax])
model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])
return model
if __name__ == '__main__':
question_maxlen, answer_maxlen = 10, 40
qa = InsuranceQA()
batch_size = 50
n_test = 10
print('Generating data...')
answers = qa.load('answers')
questions = qa.load('train')
def gen_questions(batch_size):
while True:
i = 0
question_idx = np.zeros(shape=(batch_size, question_maxlen, len(qa.vocab)))
answer_idx = np.zeros(shape=(batch_size, answer_maxlen, len(qa.vocab)))
for s in questions:
a = s['answers'][0]
answer = qa.table.encode([qa.vocab[x] for x in answers[a]], answer_maxlen)
question = qa.table.encode([qa.vocab[x] for x in s['question']], question_maxlen)
answer_idx[i] = answer
question_idx[i] = question
i += 1
if i == batch_size:
yield ([answer_idx], [question_idx])
i = 0
gen = gen_questions(batch_size)
test_gen = gen_questions(n_test)
print('Generating model...')
model = get_model(question_maxlen=question_maxlen, answer_maxlen=answer_maxlen,
vocab_len=len(qa.vocab), n_hidden=128)
print('Training model...')
for iteration in range(1, 200):
print()
print('-' * 50)
print('Iteration', iteration)
model.fit_generator(gen, samples_per_epoch=100*batch_size, nb_epoch=10)
x, y = next(test_gen)
y = y[0]
pred = model.predict(x, verbose=0)
for i in range(n_test):
print('Expected: {}'.format(qa.table.decode(y[i])))
print('Predicted: {}'.format(qa.table.decode(pred[i])))