def train(lmWithRNN, gateModel, args, trainData, validData):
if args.gpu >= 0:
lmWithRNN.lmNet.to_gpu()
gateModel.gateModel.to_gpu()
opt = O.Adam(alpha=0.001)
opt.setup(gateModel.gateModel)
opt.add_hook(chainer.optimizer.GradientClipping(args.maxGrad))
if args.weightDecay > 0:
opt.add_hook(chainer.optimizer.WeightDecay(args.weightDecay))
bestperp = np.inf
for epoch in range(args.epoch):
epochStart = time.time()
totalloss = 0
finishnum = 0
lr_decay = np.sqrt(epoch + 1)
opt.alpha = 0.001 / lr_decay
print 'Learning rate: %.6f' % (opt.alpha)
if lmWithRNN.modelType == 'RHN':
prevHidden = [
chainer.Variable(
xp.zeros((args.batch, lmWithRNN.dim)).astype(np.float32))
for _ in range(lmWithRNN.layerNum)
]
else:
prevHidden = None
for current_words, next_words in make_batch(trainData, args.batch,
args.step):
lmWithRNN.lmNet.cleargrads()
gateModel.gateModel.cleargrads()
loss, prevHidden = train_with_batch(current_words, next_words,
lmWithRNN, gateModel, args,
prevHidden)
loss.backward()
loss.unchain_backward()
opt.update()
totalloss += float(F.sum(loss).data) * current_words.shape[0]
finishnum += current_words.shape[0] * current_words.shape[1]
sys.stderr.write('\r Finished %s' % finishnum)
sys.stderr.write('\n')
epochEnd = time.time()
with chainer.no_backprop_mode(), chainer.using_config('train', False):
validloss, validperp = valid_with_batch(validData, lmWithRNN,
gateModel)
sys.stderr.write('Train time is %s\tValid time is %s\n' %
(epochEnd - epochStart, time.time() - epochEnd))
sys.stdout.write(
'Epoch: %s\tTrain loss: %.6f\tValid loss: %.6f\tValid perplexity: %.6f\n'
% (epoch, totalloss / finishnum, validloss, validperp))
sys.stdout.flush()
if validperp < bestperp:
gateOutputFile = args.output + '.bin'
S.save_npz(gateOutputFile,
copy.deepcopy(gateModel.gateModel).to_cpu())
bestperp = validperp
def train(lmWithRNN, args, trainData, validData):
if args.gpu >= 0:
lmWithRNN.lmNet.to_gpu()
if args.WT:
lmWithRNN.lmNet.Output.W.data = lmWithRNN.lmNet.Embed.W.data
#assign the same id to output and embedding
opt = O.SGD(args.lr)
opt.setup(lmWithRNN.lmNet)
opt.add_hook(chainer.optimizer.GradientClipping(args.maxGrad))
opt.add_hook(chainer.optimizer.WeightDecay(args.weight_decay))
prevvalidperp = np.inf
prevModel = None
for epoch in range(args.epoch):
epochStart = time.time()
lr_decay = args.decay**max(epoch + 1 - args.decayEpoch, 0.0)
opt.lr = args.lr * lr_decay
sys.stdout.write('Learning rate: %.6f\n' % (opt.lr))
totalloss = 0
finishnum = 0
prevHiddenList = [
chainer.Variable(
xp.zeros((args.batch, args.dim)).astype(np.float32))
for _ in range(lmWithRNN.layerNum)
]
for current_words, next_words in make_batch(trainData, args.batch,
args.step):
lmWithRNN.lmNet.cleargrads()
loss, prevHiddenList = train_with_batch(current_words, next_words,
lmWithRNN, args,
prevHiddenList)
loss.backward()
loss.unchain_backward()
opt.update()
totalloss += float(F.sum(loss).data) * current_words.shape[0]
finishnum += current_words.shape[0] * current_words.shape[1]
sys.stderr.write('\r Finished %s' % finishnum)
sys.stderr.write('\n')
epochEnd = time.time()
validloss, validperp = valid_with_batch(validData, lmWithRNN)
sys.stdout.write('Train time is %s\tValid time is %s\n' %
(epochEnd - epochStart, time.time() - epochEnd))
sys.stdout.write(
'Epoch: %s\tTrain loss: %.6f\tValid loss: %.6f\tValid perplexity: %.6f\n'
% (epoch, totalloss / finishnum, validloss, validperp))
sys.stdout.flush()
if prevvalidperp < validperp:
lmOutputFile = args.output + '.epoch%s' % (epoch) + '.bin'
S.save_npz(lmOutputFile, prevModel)
prevModel = copy.deepcopy(lmWithRNN.lmNet).to_cpu()
prevvalidperp = validperp
lmOutputFile = args.output + '.epoch%s_fin' % (epoch + 1) + '.bin'
S.save_npz(lmOutputFile, prevModel)
def valid_with_batch(validData, lmWithRNN):
batchsize = 50
prevHiddenList = [chainer.Variable(xp.zeros((batchsize, lmWithRNN.dim)).astype(np.float32)) for _ in range(lmWithRNN.layerNum)]
loss = 0
totalins = len(validData) - 1
for current_words, next_words in make_batch(validData, batchsize, 1000000):
for index in range(current_words.shape[1]):
wordIndex = current_words[:, index]
y, prevHiddenList = lmWithRNN.compute_forward(wordIndex, prevHiddenList)
loss += F.softmax_cross_entropy(y, next_words[:, index]) * batchsize
loss = float(F.sum(loss).data) / totalins
perp = np.exp(loss)
return loss, perp
def valid_with_batch(validData, lmWithRNN, gateModel):
batchsize = 64
totalins = len(validData) - 1
loss = 0
if lmWithRNN.modelType == 'RHN':
prevHidden = [
chainer.Variable(
xp.zeros((batchsize, lmWithRNN.dim)).astype(np.float32))
for _ in range(lmWithRNN.layerNum)
]
else:
prevHidden = None
for current_words, next_words in make_batch(validData, batchsize, 100000):
for index in range(current_words.shape[1]):
wordIndex = current_words[:, index]
rnn_out, prevHidden = lmWithRNN.compute_forward(
wordIndex, prevHidden)
gate = gateModel.compute_gate(wordIndex)
y = gate * rnn_out
loss += F.softmax_cross_entropy(y, next_words[:,
index]) * batchsize
loss = float(F.sum(loss).data) / totalins
perp = np.exp(loss)
return loss, perp
