def __init__(self,
in_ch,
out_ch,
kernel_size,
stride=(1, 1),
padding='VALID',
dilation=(1, 1),
bias=True):
super(Conv2d, self).__init__()
self.in_ch = in_ch
self.out_ch = out_ch
self.kernel_size = utils.pair(kernel_size)
self.stride = utils.pair(stride)
assert self.stride[0] > 0 and self.stride[1] > 0,\
'stride must be lt 0'
if isinstance(padding, str):
self.padding = padding
else:
self.padding = utils.pair(padding)
assert self.stride[0] <= self.kernel_size[0] or self.stride[0] <= self.kernel_size[1],\
'stride must be le kernel_size'
self.weight = t.Tensor(
(out_ch, in_ch, self.kernel_size[0], self.kernel_size[1]),
requires_grad=True)
self.bias = t.Tensor((out_ch, 1), requires_grad=True)
if not bias:
self.bias = None
self.reset_parameters()
def __next__(self):
if self.iterated_num * self.batch_size < self.len:
if self.start + self.batch_size > self.len:
next_start = 0
end = self.len
else:
next_start = end = self.start + self.batch_size
data = None
labels = None
for i in range(self.start, end):
if data is None:
data, labels = self.dataset[i][0].data, self.dataset[i][
1].data
else:
data = np.concatenate((data, self.dataset[i][0].data),
axis=0)
labels = np.concatenate((labels, self.dataset[i][1].data),
axis=0)
data = t.Tensor(data)
labels = t.Tensor(labels)
self.start = next_start
self.iterated_num += 1
return data, labels
else:
self.iterated_num = 0
raise StopIteration
def __init__(self, in_features, out_features, bias=True):
"""
Notes
-----
self.weight and self.bias store parameters to train
"""
super(Linear, self).__init__()
self.in_features = in_features
self.out_features = out_features
self.weight = t.Tensor((in_features, out_features), requires_grad=True)
if bias:
self.bias = t.Tensor((1, out_features), requires_grad=True)
self.reset_parameters()
def __call__(self, *args):
self.raw_inputs = list(args)
for i, arg in enumerate(args):
if arg is None:
self.raw_inputs.pop(i)
for arg in self.raw_inputs:
if isinstance(arg, t.Tensor):
self.inputs.append(arg.data)
else:
self.inputs.append(arg)
data = self.forward(*self.inputs)
requires_grad = any(
list(
map(
lambda x: x.requires_grad
if hasattr(x, 'requires_grad') else False,
self.raw_inputs)))
grad_fns = []
backward_names = get_backward_names(self)
for backward_name in backward_names:
back_name, oprand = backward_name.split('_')
oprand = int(oprand)
# wrap grad_fn by broadcast
fn = backward(self, getattr(self, backward_name))
grad_fn = GradFn(self.__class__.__name__ + back_name[0].upper() + back_name[1:] + str(oprand),\
self.raw_inputs[oprand], fn)
self.raw_inputs[oprand].grad_fn = grad_fn
grad_fns.append(grad_fn)
output_tensor = t.Tensor(data, requires_grad=requires_grad)
output_tensor._node.register_grad_fns(grad_fns)
return output_tensor
def transform(self, data):
"""
Parameters
----------
data : PIL.Image.open function returned value
format is [height, width, channels]
"""
data = np.array(data)
if data.ndim == 2:
data = data.reshape((-1, 1) + data.shape)
if data.ndim == 3:
data = data.reshape((-1, ) + data.shape)
data = np.transpose(data, (0, 3, 1, 2))
return t.Tensor(data)
def backward(self, grad=None):
"""
Parameters
----------
grad : Tensor
"""
tensor = self.tensor
if grad is None:
if self.tensor.shape == ():
grad = t.Tensor([1.0])
else:
assert False, 'need input a grad tensor when tensor is not a scalar'
if tensor.requires_grad:
tensor.grad.data = tensor.grad.data + grad.data
for grad_fn in tensor._node.grad_fns:
if t.debug.BACKWARD_TRACE:
print(grad_fn)
output_grad = grad_fn(grad.data)
grad_fn.tensor.backward(output_grad)
def backward_with_broadcast(grad):
oprand = int(wrap.__name__.split('_')[1])
ret = t.Tensor(o.broadcast(wrap(grad), oprand))
return ret
def __init__(self, gamma=1.0, beta=0.0, momentum=0.1, train=True):
super(BatchNorm2d, self).__init__()
self.gamma = t.Tensor(gamma, requires_grad=True)
self.beta = t.Tensor(beta, requires_grad=True)
self.momentum = momentum
self.training = train
def ensure_tensor(data):
if isinstance(data, t.Tensor):
return data
return t.Tensor(data)
