def get_text_data(state):
def out_format (x, y, r):
return {'x':x, 'y' :y, 'reset': r}
def out_format_valid (x, y, r):
return {'x':x, 'y' :y, 'reset': r}
train_data = LMIterator(
batch_size=state['bs'],
path = state['path'],
stop=-1,
seq_len = state['seqlen'],
mode="train",
chunks=state['chunks'],
shift = state['shift'],
output_format = out_format,
can_fit=True)
valid_data = LMIterator(
batch_size=state['bs'],
path=state['path'],
stop=-1,
use_infinite_loop=False,
allow_short_sequences = True,
seq_len= state['seqlen'],
mode="valid",
reset =state['reset'],
chunks=state['chunks'],
shift = state['shift'],
output_format = out_format_valid,
can_fit=True)
test_data = LMIterator(
batch_size=state['bs'],
path = state['path'],
stop=-1,
use_infinite_loop=False,
allow_short_sequences=True,
seq_len= state['seqlen'],
mode="test",
chunks=state['chunks'],
shift = state['shift'],
output_format = out_format_valid,
can_fit=True)
if 'wiki' in state['path']:
test_data = None
return train_data, valid_data, test_data
def get_text_data(state, path):
def out_format_test(x, y, r):
return {'x': x, 'y': y, 'reset': r}
test_data = LMIterator(batch_size=state['bs'],
path=path,
stop=-1,
use_infinite_loop=False,
allow_short_sequences=True,
seq_len=state['seqlen'],
mode="test",
chunks=state['chunks'],
shift=state['shift'],
output_format=out_format_test,
can_fit=True)
return test_data
def main():
logging.basicConfig(
level=logging.DEBUG,
format="%(asctime)s: %(name)s: %(levelname)s: %(message)s")
parser = argparse.ArgumentParser(
"Case study of language modeling with RNN",
formatter_class=argparse.ArgumentDefaultsHelpFormatter)
parser.add_argument(
"mode",
choices=["train", "sample"],
help="The mode to run. Use `train` to train a new model"
" and `sample` to sample a sequence generated by an"
" existing one.")
parser.add_argument("prefix",
default="sine",
help="The prefix for model, timing and state files")
parser.add_argument("state",
nargs="?",
default="",
help="Changes to Groundhog state")
parser.add_argument("--path", help="Path to a language dataset")
parser.add_argument("--dict", help="Path to the dataset dictionary")
parser.add_argument("--restart", help="Start anew")
parser.add_argument("--reset",
action="store_true",
default=False,
help="Reset the hidden state between batches")
parser.add_argument("--steps",
type=int,
default=100,
help="Number of steps to plot for the 'sample' mode"
" OR training sequence length for the 'train' mode.")
args = parser.parse_args()
logger.debug("Args:\n" + str(args))
dim = 200
num_chars = 50
transition = GatedRecurrent(name="transition",
activation=Tanh(),
dim=dim,
weights_init=Orthogonal())
generator = SequenceGenerator(LinearReadout(
readout_dim=num_chars,
source_names=["states"],
emitter=SoftmaxEmitter(name="emitter"),
feedbacker=LookupFeedback(num_chars, dim, name='feedback'),
name="readout"),
transition,
weights_init=IsotropicGaussian(0.01),
biases_init=Constant(0),
name="generator")
generator.allocate()
logger.debug("Parameters:\n" + pprint.pformat(
[(key, value.get_value().shape)
for key, value in Selector(generator).get_params().items()],
width=120))
if args.mode == "train":
batch_size = 1
seq_len = args.steps
generator.initialize()
# Build cost computation graph that uses the saved hidden states.
# An issue: for Groundhog this is completely transparent, that's
# why it does not carry the hidden state over the period when
# validation in done. We should find a way to fix in the future.
x = tensor.lmatrix('x')
init_states = shared_floatx_zeros((batch_size, dim),
name='init_states')
reset = tensor.scalar('reset')
cost = ComputationGraph(
generator.cost(x, states=init_states * reset).sum())
# TODO: better search routine
states = [
v for v in cost.variables if hasattr(v.tag, 'application_call')
and v.tag.application_call.brick == generator.transition and
(v.tag.application_call.application == generator.transition.apply)
and v.tag.role == VariableRole.OUTPUT and v.tag.name == 'states'
]
assert len(states) == 1
states = states[0]
gh_model = GroundhogModel(generator, cost)
gh_model.properties.append(
('bpc', cost.outputs[0] * numpy.log(2) / seq_len))
gh_model.properties.append(('mean_init_state', init_states.mean()))
gh_model.properties.append(('reset', reset))
if not args.reset:
gh_model.updates.append((init_states, states[-1]))
state = GroundhogState(args.prefix, batch_size,
learning_rate=0.0001).as_dict()
changes = eval("dict({})".format(args.state))
state.update(changes)
def output_format(x, y, reset):
return dict(x=x[:, None], reset=reset)
train, valid, test = [
LMIterator(batch_size=batch_size,
use_infinite_loop=mode == 'train',
path=args.path,
seq_len=seq_len,
mode=mode,
chunks='chars',
output_format=output_format,
can_fit=True) for mode in ['train', 'valid', 'test']
]
trainer = SGD(gh_model, state, train)
state['on_nan'] = 'warn'
state['cutoff'] = 1.
main_loop = MainLoop(train, valid, None, gh_model, trainer, state,
None)
if not args.restart:
main_loop.load()
main_loop.main()
elif args.mode == "sample":
load_params(generator, args.prefix + "model.npz")
chars = numpy.load(args.dict)['unique_chars']
sample = ComputationGraph(
generator.generate(n_steps=args.steps, batch_size=10,
iterate=True)).function()
states, outputs, costs = sample()
for i in range(10):
print("Generation cost: {}".format(costs[:, i].sum()))
print("".join([chars[o] for o in outputs[:, i]]))
else:
assert False