def _grad(self, initial=None, detach_graph=True, weight_decay=None, **kwargs):
'''This method follows computational graph and returns the gradients of
Variable object.
Args:
initial (ndarray): Initial value of following the graph.
detach_graph (bool): If it's True, the computational graph will be destroyed.
weight_decay (float): Sets the default weight decay of the model.
See the Variable class for more info.
'''
if not self._has_autoupdate():
return Grads()
if initial is None:
if self.size > 1:
raise ValueError("Initial diff is required for scalar value.")
if is_cuda_active():
initial = Node(get_gpu(self).ones_like_me())
else:
initial = np.ones_like(self).astype(precision)
context = Grads(self, weight_decay=weight_decay)
self._update_diff(context, initial, **kwargs)
if detach_graph:
self.detach_graph()
return context
def _backward_gpu(self, context, dy, **kwargs):
dy.to_cpu()
cu.set_cuda_active(False)
dx = imnpool(self.attrs._original_x, self.attrs._kernel, self.attrs._stride,
self.attrs._padding, mode="max", alternate_input=dy)
cu.set_cuda_active(True)
dx = Node(dx)
self.attrs._x._update_diff(context, dx)
def gpu_check(opt):
node = Variable(np.array(np.random.rand(3, 3, 3, 3), dtype=precision))
grad = Variable(np.array(np.random.rand(3, 3, 3, 3), dtype=precision))
set_cuda_active(False)
for _ in range(3):
opt(grad, node)
dy_cpu = opt(grad, node)
assert isinstance(dy_cpu, Node)
opt.reset()
set_cuda_active(True)
for _ in range(3):
opt(grad, node)
dy_gpu = opt(grad, node)
assert isinstance(dy_gpu, GPUValue)
dy_gpu = Node(dy_gpu)
dy_gpu.to_cpu()
close(dy_gpu, dy_cpu)
def join_grads(self, grads, others):
"""Merge gradients of other models.
Others is a list of tuple of (model, grads) to be merged.
Models listed in the others should have same structure with self."""
values = {
name: params
for name, params, attrs in self.flatten_values()
}
for model, _grads in others:
o = model._get_grads(_grads)
for (name, attrname), diff in o.items():
obj = values[name][attrname]
curdiff = grads.get(obj, None)
if curdiff is not None:
if not isinstance(curdiff, Node):
curdiff = Node(curdiff)
if not isinstance(diff, Node):
diff = Node(diff)
with use_device(curdiff.device_id):
if GPUValue is not None and diff.device_id != curdiff.device_id:
g = GPUValue(shape=diff.shape)
g.copy_from(diff.get_gpu())
diff = Node(g)
newdiff = curdiff + diff
grads.set(obj, newdiff)
def load(self, filename):
"""Load saved weights to model.
Args:
filename (str): File name of saved model.
Example:
>>> model = rm.Dense(2)
>>> model.load("model.hd5")
"""
import h5py
f = h5py.File(filename, 'r')
values = f['values']
types = f['types']
names = sorted(values.keys())
def get_attr(root, names):
names = names.split('.')[1:]
ret = root
for name in names:
ret = getattr(ret, name)
return ret
target = self
for name in names:
target = get_attr(self, name)
values_grp = values[name]
types_grp = types[name]
for k, v in values_grp.items():
v = v.value
if isinstance(v, np.ndarray):
type = types_grp.get(k, None)
if type:
if type.value == 'renom.Variable':
auto_update = types_grp[k + '._auto_update'].value
v = Variable(v, auto_update=auto_update)
else:
v = Node(v)
if k.startswith('__dict__.'):
obj = target
name = k.split(".", 1)[1]
else:
obj = target.params
name = k
setattr(obj, name, v)
def train(self, train_distributor, test_distributor=None):
"""Train method.
This method executes train loop.
If test_distributor is given, validation loss will be calculated.
Args:
train_distributor (Distributor): Distributor for yielding train data.
test_distributor (Distributor): Distributor for yielding test data.
"""
self.epoch = 0
self.train_distributor = train_distributor
self.test_distributor = test_distributor
self.on_event('start')
self.train_loss_list = []
self.test_loss_list = []
models = [self.model]
if self.num_gpu > 1:
models.extend(
[self.model.__class__() for _ in range(self.num_gpu - 1)])
for n in range(self.num_gpu):
models[n].set_gpu(n)
while self.epoch < self.num_epoch:
self.on_event('start_epoch')
self.nth = 0
self.avg_train_loss = 0
for iteration, (data, target) in enumerate(
self.train_distributor.batch(self.batch_size,
self.shuffle)):
datalen = len(data) // len(models)
self.data = [
data[i:i + datalen]
for i in range(0, datalen * len(models), datalen)
]
if is_cuda_active():
self.data = [Node(d) for d in self.data]
for n, d in enumerate(self.data):
with use_device(n):
d.to_gpu()
targetlen = len(target) // len(models)
self.targets = [
target[i:i + targetlen]
for i in range(0, targetlen * len(models), targetlen)
]
if is_cuda_active():
self.targets = [Node(d) for d in self.targets]
for n, d in enumerate(self.targets):
with use_device(n):
d.to_gpu()
for gpu in range(1, self.num_gpu):
models[gpu].copy_params(models[0])
for gpu in range(0, self.num_gpu):
models[gpu].set_models(inference=False)
self.on_event('forward')
self.outputs = []
for gpu in range(self.num_gpu):
model = models[gpu]
with model.train():
self.outputs.append(model(self.data[gpu]))
self.on_event('loss')
self.losses = []
for gpu in range(self.num_gpu):
model = models[gpu]
with use_device(gpu):
self.losses.append(
self.loss_func(self.outputs[gpu],
self.targets[gpu]))
self.avg_train_loss += (self.losses[0] -
self.avg_train_loss) / (iteration + 1)
self.on_event('backward')
self.grads = []
for gpu in range(self.num_gpu):
model = models[gpu]
with use_device(gpu):
self.grads.append(self.losses[gpu].grad())
self.on_event('grad')
if self.num_gpu > 1:
models[0].join_grads(self.grads[0],
zip(models[1:], self.grads[1:]))
self.grads[0].update(self.optimizer)
self.on_event('updated')
self.nth += 1
self.on_event('end_epoch')
self.epoch += 1
# release objects
self.data = self.target = None
self.outputs = self.losses = self.grads = None
self.avg_train_loss = None
def preload_single(batch):
with cu.asyncBehaviour():
batch = batch.astype(np.dtype(precision))
cu.pinNumpy(batch)
ret = Node(get_gpu(batch))
return ret
def store(self, node, dy):
selfid = id(node)
self.stroage[selfid] = Node(
dy) # if cuda active, dy must be GPUValue type.
