def test_unpickle_key():
fd, fname = tempfile.mkstemp()
with os.fdopen(fd, 'wb') as f:
d = ('a', 1)
cPickle.dump(d, f)
loaded = load("{!pkl: '%s': 50}" % fname)
assert_(first_key(loaded) == d)
assert_(first_value(loaded) == 50)
os.remove(fname)
def test_unpickle_key():
fd, fname = tempfile.mkstemp()
with os.fdopen(fd, 'wb') as f:
d = ('a', 1)
cPickle.dump(d, f)
loaded = load("{!pkl: '%s': 50}" % fname)
assert_(first_key(loaded) == d)
assert_(first_value(loaded) == 50)
os.remove(fname)
def setup(self, model, dataset):
"""
Allows the training algorithm to do some preliminary configuration
*before* we actually start training the model. The dataset is provided
in case other derived training algorithms need to modify model based on
the dataset.
Parameters
----------
model : object
A Python object representing the model to train. Loosely
implementing the interface of models.model.Model.
dataset : pylearn2.datasets.dataset.Dataset
Dataset object used to draw training data
"""
self.model = model
if self.cost is None:
self.cost = model.get_default_cost()
try:
if self.cost.is_stochastic():
raise TypeError("BGD is not compatible with stochastic "
"costs.")
except NotImplementedError:
warnings.warn("BGD is not compatible with stochastic costs "
"and cannot determine whether the current cost is "
"stochastic.")
if self.batch_size is None:
self.batch_size = model.force_batch_size
else:
batch_size = self.batch_size
if self.set_batch_size:
model.set_batch_size(batch_size)
elif hasattr(model, 'force_batch_size'):
if not (model.force_batch_size is None or
model.force_batch_size <= 0 or
batch_size == model.force_batch_size):
raise ValueError("batch_size is %d but " +
"model.force_batch_size is %d" %
(batch_size, model.force_batch_size))
self.monitor = Monitor.get_monitor(model)
self.monitor.set_theano_function_mode(self.theano_function_mode)
data_specs = self.cost.get_data_specs(model)
mapping = DataSpecsMapping(data_specs)
space_tuple = mapping.flatten(data_specs[0], return_tuple=True)
source_tuple = mapping.flatten(data_specs[1], return_tuple=True)
# Build a flat tuple of Theano Variables, one for each space,
# named according to the sources.
theano_args = []
for space, source in safe_zip(space_tuple, source_tuple):
name = 'BGD_[%s]' % source
arg = space.make_theano_batch(name=name)
theano_args.append(arg)
theano_args = tuple(theano_args)
# Methods of `self.cost` need args to be passed in a format compatible
# with their data_specs
nested_args = mapping.nest(theano_args)
fixed_var_descr = self.cost.get_fixed_var_descr(model, nested_args)
self.on_load_batch = fixed_var_descr.on_load_batch
cost_value = self.cost.expr(model, nested_args,
** fixed_var_descr.fixed_vars)
grads, grad_updates = self.cost.get_gradients(
model, nested_args, ** fixed_var_descr.fixed_vars)
assert isinstance(grads, OrderedDict)
assert isinstance(grad_updates, OrderedDict)
if cost_value is None:
raise ValueError("BGD is incompatible with " + str(self.cost) +
" because it is intractable, but BGD uses the " +
"cost function value to do line searches.")
# obj_prereqs has to be a list of function f called with f(*data),
# where data is a data tuple coming from the iterator.
# this function enables capturing "mapping" and "f", while
# enabling the "*data" syntax
def capture(f, mapping=mapping):
new_f = lambda *args: f(mapping.flatten(args, return_tuple=True))
return new_f
obj_prereqs = [capture(f) for f in fixed_var_descr.on_load_batch]
if self.monitoring_dataset is not None:
if (self.monitoring_batch_size is None and
self.monitoring_batches is None):
self.monitoring_batch_size = self.batch_size
self.monitoring_batches = self.batches_per_iter
self.monitor.setup(
dataset=self.monitoring_dataset,
cost=self.cost,
batch_size=self.monitoring_batch_size,
num_batches=self.monitoring_batches,
obj_prereqs=obj_prereqs,
cost_monitoring_args=fixed_var_descr.fixed_vars)
params = model.get_params()
self.optimizer = BatchGradientDescent(
objective=cost_value,
gradients=grads,
gradient_updates=grad_updates,
params=params,
param_constrainers=[model.modify_updates],
lr_scalers=model.get_lr_scalers(),
inputs=theano_args,
verbose=self.verbose_optimization,
max_iter=self.updates_per_batch,
reset_alpha=self.reset_alpha,
conjugate=self.conjugate,
reset_conjugate=self.reset_conjugate,
min_init_alpha=self.min_init_alpha,
line_search_mode=self.line_search_mode,
theano_function_mode=self.theano_function_mode,
init_alpha=self.init_alpha)
# These monitoring channels keep track of shared variables,
# which do not need inputs nor data.
if self.monitoring_dataset is not None:
self.monitor.add_channel(
name='ave_step_size',
ipt=None,
val=self.optimizer.ave_step_size,
data_specs=(NullSpace(), ''),
dataset=first_value(self.monitoring_dataset))
self.monitor.add_channel(
name='ave_grad_size',
ipt=None,
val=self.optimizer.ave_grad_size,
data_specs=(NullSpace(), ''),
dataset=first_value(self.monitoring_dataset))
self.monitor.add_channel(
name='ave_grad_mult',
ipt=None,
val=self.optimizer.ave_grad_mult,
data_specs=(NullSpace(), ''),
dataset=first_value(self.monitoring_dataset))
self.first = True
self.bSetup = True
