torch.Tensor¶
A torch.Tensor is a multi-dimensional matrix containing elements of
a single data type.
Torch defines 10 tensor types with CPU and GPU variants which are as follows:
Data type |
dtype |
CPU tensor |
GPU tensor |
|---|---|---|---|
32-bit floating point |
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64-bit floating point |
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16-bit floating point 1 |
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16-bit floating point 2 |
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32-bit complex |
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64-bit complex |
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128-bit complex |
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8-bit integer (unsigned) |
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8-bit integer (signed) |
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16-bit integer (signed) |
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32-bit integer (signed) |
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64-bit integer (signed) |
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Boolean |
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- 1
Sometimes referred to as binary16: uses 1 sign, 5 exponent, and 10 significand bits. Useful when precision is important at the expense of range.
- 2
Sometimes referred to as Brain Floating Point: uses 1 sign, 8 exponent, and 7 significand bits. Useful when range is important, since it has the same number of exponent bits as
float32
torch.Tensor is an alias for the default tensor type (torch.FloatTensor).
A tensor can be constructed from a Python list or sequence using the
torch.tensor() constructor:
>>> torch.tensor([[1., -1.], [1., -1.]])
tensor([[ 1.0000, -1.0000],
[ 1.0000, -1.0000]])
>>> torch.tensor(np.array([[1, 2, 3], [4, 5, 6]]))
tensor([[ 1, 2, 3],
[ 4, 5, 6]])
Warning
torch.tensor() always copies data. If you have a Tensor
data and just want to change its requires_grad flag, use
requires_grad_() or
detach() to avoid a copy.
If you have a numpy array and want to avoid a copy, use
torch.as_tensor().
A tensor of specific data type can be constructed by passing a
torch.dtype and/or a torch.device to a
constructor or tensor creation op:
>>> torch.zeros([2, 4], dtype=torch.int32)
tensor([[ 0, 0, 0, 0],
[ 0, 0, 0, 0]], dtype=torch.int32)
>>> cuda0 = torch.device('cuda:0')
>>> torch.ones([2, 4], dtype=torch.float64, device=cuda0)
tensor([[ 1.0000, 1.0000, 1.0000, 1.0000],
[ 1.0000, 1.0000, 1.0000, 1.0000]], dtype=torch.float64, device='cuda:0')
The contents of a tensor can be accessed and modified using Python’s indexing and slicing notation:
>>> x = torch.tensor([[1, 2, 3], [4, 5, 6]])
>>> print(x[1][2])
tensor(6)
>>> x[0][1] = 8
>>> print(x)
tensor([[ 1, 8, 3],
[ 4, 5, 6]])
Use torch.Tensor.item() to get a Python number from a tensor containing a
single value:
>>> x = torch.tensor([[1]])
>>> x
tensor([[ 1]])
>>> x.item()
1
>>> x = torch.tensor(2.5)
>>> x
tensor(2.5000)
>>> x.item()
2.5
A tensor can be created with requires_grad=True so that
torch.autograd records operations on them for automatic differentiation.
>>> x = torch.tensor([[1., -1.], [1., 1.]], requires_grad=True)
>>> out = x.pow(2).sum()
>>> out.backward()
>>> x.grad
tensor([[ 2.0000, -2.0000],
[ 2.0000, 2.0000]])
Each tensor has an associated torch.Storage, which holds its data.
The tensor class also provides multi-dimensional, strided
view of a storage and defines numeric operations on it.
Note
For more information on tensor views, see Tensor Views.
Note
For more information on the torch.dtype, torch.device, and
torch.layout attributes of a torch.Tensor, see
Tensor Attributes.
Note
Methods which mutate a tensor are marked with an underscore suffix.
For example, torch.FloatTensor.abs_() computes the absolute value
in-place and returns the modified tensor, while torch.FloatTensor.abs()
computes the result in a new tensor.
Note
To change an existing tensor’s torch.device and/or torch.dtype, consider using
to() method on the tensor.
Warning
Current implementation of torch.Tensor introduces memory overhead,
thus it might lead to unexpectedly high memory usage in the applications with many tiny tensors.
If this is your case, consider using one large structure.
-
class
torch.Tensor¶ There are a few main ways to create a tensor, depending on your use case.
To create a tensor with pre-existing data, use
torch.tensor().To create a tensor with specific size, use
torch.*tensor creation ops (see Creation Ops).To create a tensor with the same size (and similar types) as another tensor, use
torch.*_liketensor creation ops (see Creation Ops).To create a tensor with similar type but different size as another tensor, use
tensor.new_*creation ops.
-
new_tensor(data, dtype=None, device=None, requires_grad=False) → Tensor¶ Returns a new Tensor with
dataas the tensor data. By default, the returned Tensor has the sametorch.dtypeandtorch.deviceas this tensor.Warning
new_tensor()always copiesdata. If you have a Tensordataand want to avoid a copy, usetorch.Tensor.requires_grad_()ortorch.Tensor.detach(). If you have a numpy array and want to avoid a copy, usetorch.from_numpy().Warning
When data is a tensor x,
new_tensor()reads out ‘the data’ from whatever it is passed, and constructs a leaf variable. Thereforetensor.new_tensor(x)is equivalent tox.clone().detach()andtensor.new_tensor(x, requires_grad=True)is equivalent tox.clone().detach().requires_grad_(True). The equivalents usingclone()anddetach()are recommended.- Parameters
data (array_like) – The returned Tensor copies
data.dtype (
torch.dtype, optional) – the desired type of returned tensor. Default: if None, sametorch.dtypeas this tensor.device (
torch.device, optional) – the desired device of returned tensor. Default: if None, sametorch.deviceas this tensor.requires_grad (bool, optional) – If autograd should record operations on the returned tensor. Default:
False.
Example:
>>> tensor = torch.ones((2,), dtype=torch.int8) >>> data = [[0, 1], [2, 3]] >>> tensor.new_tensor(data) tensor([[ 0, 1], [ 2, 3]], dtype=torch.int8)
-
new_full(size, fill_value, dtype=None, device=None, requires_grad=False) → Tensor¶ Returns a Tensor of size
sizefilled withfill_value. By default, the returned Tensor has the sametorch.dtypeandtorch.deviceas this tensor.- Parameters
fill_value (scalar) – the number to fill the output tensor with.
dtype (
torch.dtype, optional) – the desired type of returned tensor. Default: if None, sametorch.dtypeas this tensor.device (
torch.device, optional) – the desired device of returned tensor. Default: if None, sametorch.deviceas this tensor.requires_grad (bool, optional) – If autograd should record operations on the returned tensor. Default:
False.
Example:
>>> tensor = torch.ones((2,), dtype=torch.float64) >>> tensor.new_full((3, 4), 3.141592) tensor([[ 3.1416, 3.1416, 3.1416, 3.1416], [ 3.1416, 3.1416, 3.1416, 3.1416], [ 3.1416, 3.1416, 3.1416, 3.1416]], dtype=torch.float64)
-
new_empty(size, dtype=None, device=None, requires_grad=False) → Tensor¶ Returns a Tensor of size
sizefilled with uninitialized data. By default, the returned Tensor has the sametorch.dtypeandtorch.deviceas this tensor.- Parameters
dtype (
torch.dtype, optional) – the desired type of returned tensor. Default: if None, sametorch.dtypeas this tensor.device (
torch.device, optional) – the desired device of returned tensor. Default: if None, sametorch.deviceas this tensor.requires_grad (bool, optional) – If autograd should record operations on the returned tensor. Default:
False.
Example:
>>> tensor = torch.ones(()) >>> tensor.new_empty((2, 3)) tensor([[ 5.8182e-18, 4.5765e-41, -1.0545e+30], [ 3.0949e-41, 4.4842e-44, 0.0000e+00]])
-
new_ones(size, dtype=None, device=None, requires_grad=False) → Tensor¶ Returns a Tensor of size
sizefilled with1. By default, the returned Tensor has the sametorch.dtypeandtorch.deviceas this tensor.- Parameters
size (int...) – a list, tuple, or
torch.Sizeof integers defining the shape of the output tensor.dtype (
torch.dtype, optional) – the desired type of returned tensor. Default: if None, sametorch.dtypeas this tensor.device (
torch.device, optional) – the desired device of returned tensor. Default: if None, sametorch.deviceas this tensor.requires_grad (bool, optional) – If autograd should record operations on the returned tensor. Default:
False.
Example:
>>> tensor = torch.tensor((), dtype=torch.int32) >>> tensor.new_ones((2, 3)) tensor([[ 1, 1, 1], [ 1, 1, 1]], dtype=torch.int32)
-
new_zeros(size, dtype=None, device=None, requires_grad=False) → Tensor¶ Returns a Tensor of size
sizefilled with0. By default, the returned Tensor has the sametorch.dtypeandtorch.deviceas this tensor.- Parameters
size (int...) – a list, tuple, or
torch.Sizeof integers defining the shape of the output tensor.dtype (
torch.dtype, optional) – the desired type of returned tensor. Default: if None, sametorch.dtypeas this tensor.device (
torch.device, optional) – the desired device of returned tensor. Default: if None, sametorch.deviceas this tensor.requires_grad (bool, optional) – If autograd should record operations on the returned tensor. Default:
False.
Example:
>>> tensor = torch.tensor((), dtype=torch.float64) >>> tensor.new_zeros((2, 3)) tensor([[ 0., 0., 0.], [ 0., 0., 0.]], dtype=torch.float64)
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is_cuda¶ Is
Trueif the Tensor is stored on the GPU,Falseotherwise.
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is_quantized¶ Is
Trueif the Tensor is quantized,Falseotherwise.
-
is_meta¶ Is
Trueif the Tensor is a meta tensor,Falseotherwise. Meta tensors are like normal tensors, but they carry no data.
-
device¶ Is the
torch.devicewhere this Tensor is.
-
grad This attribute is
Noneby default and becomes a Tensor the first time a call tobackward()computes gradients forself. The attribute will then contain the gradients computed and future calls tobackward()will accumulate (add) gradients into it.
-
T¶ Is this Tensor with its dimensions reversed.
If
nis the number of dimensions inx,x.Tis equivalent tox.permute(n-1, n-2, ..., 0).
-
real¶ Returns a new tensor containing real values of the
selftensor. The returned tensor andselfshare the same underlying storage.Warning
real()is only supported for tensors with complex dtypes.- Example::
>>> x=torch.randn(4, dtype=torch.cfloat) >>> x tensor([(0.3100+0.3553j), (-0.5445-0.7896j), (-1.6492-0.0633j), (-0.0638-0.8119j)]) >>> x.real tensor([ 0.3100, -0.5445, -1.6492, -0.0638])
-
imag¶ Returns a new tensor containing imaginary values of the
selftensor. The returned tensor andselfshare the same underlying storage.Warning
imag()is only supported for tensors with complex dtypes.- Example::
>>> x=torch.randn(4, dtype=torch.cfloat) >>> x tensor([(0.3100+0.3553j), (-0.5445-0.7896j), (-1.6492-0.0633j), (-0.0638-0.8119j)]) >>> x.imag tensor([ 0.3553, -0.7896, -0.0633, -0.8119])
-
abs() → Tensor¶ See
torch.abs()
-
absolute_() → Tensor¶ In-place version of
absolute()Alias forabs_()
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acos() → Tensor¶ See
torch.acos()
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arccos() → Tensor¶ See
torch.arccos()
-
add(other, *, alpha=1) → Tensor¶ Add a scalar or tensor to
selftensor. If bothalphaandotherare specified, each element ofotheris scaled byalphabefore being used.When
otheris a tensor, the shape ofothermust be broadcastable with the shape of the underlying tensorSee
torch.add()
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addbmm(batch1, batch2, *, beta=1, alpha=1) → Tensor¶ See
torch.addbmm()
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addcdiv(tensor1, tensor2, *, value=1) → Tensor¶ See
torch.addcdiv()
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addcmul(tensor1, tensor2, *, value=1) → Tensor¶ See
torch.addcmul()
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addmm(mat1, mat2, *, beta=1, alpha=1) → Tensor¶ See
torch.addmm()
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sspaddmm(mat1, mat2, *, beta=1, alpha=1) → Tensor See
torch.sspaddmm()
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addmv(mat, vec, *, beta=1, alpha=1) → Tensor¶ See
torch.addmv()
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addr(vec1, vec2, *, beta=1, alpha=1) → Tensor¶ See
torch.addr()
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allclose(other, rtol=1e-05, atol=1e-08, equal_nan=False) → Tensor¶ See
torch.allclose()
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amax(dim=None, keepdim=False) → Tensor¶ See
torch.amax()
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amin(dim=None, keepdim=False) → Tensor¶ See
torch.amin()
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angle() → Tensor¶ See
torch.angle()
-
apply_(callable) → Tensor¶ Applies the function
callableto each element in the tensor, replacing each element with the value returned bycallable.Note
This function only works with CPU tensors and should not be used in code sections that require high performance.
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argmax(dim=None, keepdim=False) → LongTensor¶ See
torch.argmax()
-
argmin(dim=None, keepdim=False) → LongTensor¶ See
torch.argmin()
-
argsort(dim=- 1, descending=False) → LongTensor¶ See
torch.argsort()
-
asin() → Tensor¶ See
torch.asin()
-
arcsin() → Tensor¶ See
torch.arcsin()
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as_strided(size, stride, storage_offset=0) → Tensor¶
-
atan() → Tensor¶ See
torch.atan()
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arctan() → Tensor¶ See
torch.arctan()
-
atan2(other) → Tensor¶ See
torch.atan2()
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all(dim=None, keepdim=False) → Tensor¶ See
torch.all()
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any(dim=None, keepdim=False) → Tensor¶ See
torch.any()
-
backward(gradient=None, retain_graph=None, create_graph=False, inputs=None)[source] Computes the gradient of current tensor w.r.t. graph leaves.
The graph is differentiated using the chain rule. If the tensor is non-scalar (i.e. its data has more than one element) and requires gradient, the function additionally requires specifying
gradient. It should be a tensor of matching type and location, that contains the gradient of the differentiated function w.r.t.self.This function accumulates gradients in the leaves - you might need to zero
.gradattributes or set them toNonebefore calling it. See Default gradient layouts for details on the memory layout of accumulated gradients.Note
If you run any forward ops, create
gradient, and/or callbackwardin a user-specified CUDA stream context, see Stream semantics of backward passes.- Parameters
gradient (Tensor or None) – Gradient w.r.t. the tensor. If it is a tensor, it will be automatically converted to a Tensor that does not require grad unless
create_graphis True. None values can be specified for scalar Tensors or ones that don’t require grad. If a None value would be acceptable then this argument is optional.retain_graph (bool, optional) – If
False, the graph used to compute the grads will be freed. Note that in nearly all cases setting this option to True is not needed and often can be worked around in a much more efficient way. Defaults to the value ofcreate_graph.create_graph (bool, optional) – If
True, graph of the derivative will be constructed, allowing to compute higher order derivative products. Defaults toFalse.inputs (sequence of Tensor) – Inputs w.r.t. which the gradient will be accumulated into
.grad. All other Tensors will be ignored. If not provided, the gradient is accumulated into all the leaf Tensors that were used to compute the attr::tensors. All the provided inputs must be leaf Tensors.
-
baddbmm(batch1, batch2, *, beta=1, alpha=1) → Tensor¶ See
torch.baddbmm()
-
bernoulli(*, generator=None) → Tensor¶ Returns a result tensor where each is independently sampled from .
selfmust have floating pointdtype, and the result will have the samedtype.
-
bernoulli_()¶ -
bernoulli_(p=0.5, *, generator=None) → Tensor¶ Fills each location of
selfwith an independent sample from .selfcan have integraldtype.
-
bernoulli_(p_tensor, *, generator=None) → Tensor¶ p_tensorshould be a tensor containing probabilities to be used for drawing the binary random number.The element of
selftensor will be set to a value sampled from .selfcan have integraldtype, butp_tensormust have floating pointdtype.
See also
bernoulli()andtorch.bernoulli()-
-
bfloat16(memory_format=torch.preserve_format) → Tensor¶ self.bfloat16()is equivalent toself.to(torch.bfloat16). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
bincount(weights=None, minlength=0) → Tensor¶ See
torch.bincount()
-
bitwise_not() → Tensor¶
-
bitwise_not_() → Tensor¶ In-place version of
bitwise_not()
-
bitwise_and() → Tensor¶
-
bitwise_and_() → Tensor¶ In-place version of
bitwise_and()
-
bitwise_or() → Tensor¶
-
bitwise_or_() → Tensor¶ In-place version of
bitwise_or()
-
bitwise_xor() → Tensor¶
-
bitwise_xor_() → Tensor¶ In-place version of
bitwise_xor()
-
bmm(batch2) → Tensor¶ See
torch.bmm()
-
bool(memory_format=torch.preserve_format) → Tensor¶ self.bool()is equivalent toself.to(torch.bool). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
byte(memory_format=torch.preserve_format) → Tensor¶ self.byte()is equivalent toself.to(torch.uint8). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
broadcast_to(shape) → Tensor¶ See
torch.broadcast_to().
-
cauchy_(median=0, sigma=1, *, generator=None) → Tensor¶ Fills the tensor with numbers drawn from the Cauchy distribution:
-
ceil() → Tensor¶ See
torch.ceil()
-
char(memory_format=torch.preserve_format) → Tensor¶ self.char()is equivalent toself.to(torch.int8). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
cholesky(upper=False) → Tensor¶ See
torch.cholesky()
-
cholesky_inverse(upper=False) → Tensor¶
-
cholesky_solve(input2, upper=False) → Tensor¶
-
chunk(chunks, dim=0) → List of Tensors¶ See
torch.chunk()
-
clamp(min, max) → Tensor¶ See
torch.clamp()
-
clone(*, memory_format=torch.preserve_format) → Tensor¶ See
torch.clone()
-
contiguous(memory_format=torch.contiguous_format) → Tensor¶ Returns a contiguous in memory tensor containing the same data as
selftensor. Ifselftensor is already in the specified memory format, this function returns theselftensor.- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.contiguous_format.
-
copy_(src, non_blocking=False) → Tensor¶ Copies the elements from
srcintoselftensor and returnsself.The
srctensor must be broadcastable with theselftensor. It may be of a different data type or reside on a different device.
-
conj() → Tensor¶ See
torch.conj()
-
copysign(other) → Tensor¶ See
torch.copysign()
-
copysign_(other) → Tensor¶ In-place version of
copysign()
-
cos() → Tensor¶ See
torch.cos()
-
cosh() → Tensor¶ See
torch.cosh()
-
count_nonzero(dim=None) → Tensor¶
-
acosh() → Tensor¶ See
torch.acosh()
-
arccosh()¶ acosh() -> Tensor
See
torch.arccosh()
-
cpu(memory_format=torch.preserve_format) → Tensor¶ Returns a copy of this object in CPU memory.
If this object is already in CPU memory and on the correct device, then no copy is performed and the original object is returned.
- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
cross(other, dim=- 1) → Tensor¶ See
torch.cross()
-
cuda(device=None, non_blocking=False, memory_format=torch.preserve_format) → Tensor¶ Returns a copy of this object in CUDA memory.
If this object is already in CUDA memory and on the correct device, then no copy is performed and the original object is returned.
- Parameters
device (
torch.device) – The destination GPU device. Defaults to the current CUDA device.non_blocking (bool) – If
Trueand the source is in pinned memory, the copy will be asynchronous with respect to the host. Otherwise, the argument has no effect. Default:False.memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
logcumsumexp(dim) → Tensor¶
-
cummax(dim)¶ See
torch.cummax()
-
cummin(dim)¶ See
torch.cummin()
-
cumprod(dim, dtype=None) → Tensor¶ See
torch.cumprod()
-
cumsum(dim, dtype=None) → Tensor¶ See
torch.cumsum()
-
deg2rad() → Tensor¶ See
torch.deg2rad()
-
dequantize() → Tensor¶ Given a quantized Tensor, dequantize it and return the dequantized float Tensor.
-
det() → Tensor¶ See
torch.det()
-
dense_dim() → int Return the number of dense dimensions in a sparse tensor
self.Warning
Throws an error if
selfis not a sparse tensor.See also
Tensor.sparse_dim()and hybrid tensors.
-
detach() Returns a new Tensor, detached from the current graph.
The result will never require gradient.
Note
Returned Tensor shares the same storage with the original one. In-place modifications on either of them will be seen, and may trigger errors in correctness checks. IMPORTANT NOTE: Previously, in-place size / stride / storage changes (such as resize_ / resize_as_ / set_ / transpose_) to the returned tensor also update the original tensor. Now, these in-place changes will not update the original tensor anymore, and will instead trigger an error. For sparse tensors: In-place indices / values changes (such as zero_ / copy_ / add_) to the returned tensor will not update the original tensor anymore, and will instead trigger an error.
-
detach_() Detaches the Tensor from the graph that created it, making it a leaf. Views cannot be detached in-place.
-
diag(diagonal=0) → Tensor¶ See
torch.diag()
-
diag_embed(offset=0, dim1=- 2, dim2=- 1) → Tensor¶
-
diagflat(offset=0) → Tensor¶ See
torch.diagflat()
-
diagonal(offset=0, dim1=0, dim2=1) → Tensor¶ See
torch.diagonal()
-
fill_diagonal_(fill_value, wrap=False) → Tensor¶ Fill the main diagonal of a tensor that has at least 2-dimensions. When dims>2, all dimensions of input must be of equal length. This function modifies the input tensor in-place, and returns the input tensor.
- Parameters
fill_value (Scalar) – the fill value
wrap (bool) – the diagonal ‘wrapped’ after N columns for tall matrices.
Example:
>>> a = torch.zeros(3, 3) >>> a.fill_diagonal_(5) tensor([[5., 0., 0.], [0., 5., 0.], [0., 0., 5.]]) >>> b = torch.zeros(7, 3) >>> b.fill_diagonal_(5) tensor([[5., 0., 0.], [0., 5., 0.], [0., 0., 5.], [0., 0., 0.], [0., 0., 0.], [0., 0., 0.], [0., 0., 0.]]) >>> c = torch.zeros(7, 3) >>> c.fill_diagonal_(5, wrap=True) tensor([[5., 0., 0.], [0., 5., 0.], [0., 0., 5.], [0., 0., 0.], [5., 0., 0.], [0., 5., 0.], [0., 0., 5.]])
-
fmax(other) → Tensor¶ See
torch.fmax()
-
fmin(other) → Tensor¶ See
torch.fmin()
-
digamma() → Tensor¶ See
torch.digamma()
-
dist(other, p=2) → Tensor¶ See
torch.dist()
-
div(value) → Tensor¶ See
torch.div()
-
divide(value) → Tensor¶ See
torch.divide()
-
dot(other) → Tensor¶ See
torch.dot()
-
double(memory_format=torch.preserve_format) → Tensor¶ self.double()is equivalent toself.to(torch.float64). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
eig(eigenvectors=False)¶ See
torch.eig()
-
element_size() → int¶ Returns the size in bytes of an individual element.
Example:
>>> torch.tensor([]).element_size() 4 >>> torch.tensor([], dtype=torch.uint8).element_size() 1
-
eq(other) → Tensor¶ See
torch.eq()
-
equal(other) → bool¶ See
torch.equal()
-
erf() → Tensor¶ See
torch.erf()
-
erfc() → Tensor¶ See
torch.erfc()
-
erfinv() → Tensor¶ See
torch.erfinv()
-
exp() → Tensor¶ See
torch.exp()
-
expm1() → Tensor¶ See
torch.expm1()
-
expand(*sizes) → Tensor¶ Returns a new view of the
selftensor with singleton dimensions expanded to a larger size.Passing -1 as the size for a dimension means not changing the size of that dimension.
Tensor can be also expanded to a larger number of dimensions, and the new ones will be appended at the front. For the new dimensions, the size cannot be set to -1.
Expanding a tensor does not allocate new memory, but only creates a new view on the existing tensor where a dimension of size one is expanded to a larger size by setting the
strideto 0. Any dimension of size 1 can be expanded to an arbitrary value without allocating new memory.- Parameters
*sizes (torch.Size or int...) – the desired expanded size
Warning
More than one element of an expanded tensor may refer to a single memory location. As a result, in-place operations (especially ones that are vectorized) may result in incorrect behavior. If you need to write to the tensors, please clone them first.
Example:
>>> x = torch.tensor([[1], [2], [3]]) >>> x.size() torch.Size([3, 1]) >>> x.expand(3, 4) tensor([[ 1, 1, 1, 1], [ 2, 2, 2, 2], [ 3, 3, 3, 3]]) >>> x.expand(-1, 4) # -1 means not changing the size of that dimension tensor([[ 1, 1, 1, 1], [ 2, 2, 2, 2], [ 3, 3, 3, 3]])
-
expand_as(other) → Tensor¶ Expand this tensor to the same size as
other.self.expand_as(other)is equivalent toself.expand(other.size()).Please see
expand()for more information aboutexpand.- Parameters
other (
torch.Tensor) – The result tensor has the same size asother.
-
exponential_(lambd=1, *, generator=None) → Tensor¶ Fills
selftensor with elements drawn from the exponential distribution:
-
fix() → Tensor¶ See
torch.fix().
-
fill_(value) → Tensor¶ Fills
selftensor with the specified value.
-
flatten(input, start_dim=0, end_dim=- 1) → Tensor¶ see
torch.flatten()
-
flip(dims) → Tensor¶ See
torch.flip()
-
fliplr() → Tensor¶ See
torch.fliplr()
-
flipud() → Tensor¶ See
torch.flipud()
-
float(memory_format=torch.preserve_format) → Tensor¶ self.float()is equivalent toself.to(torch.float32). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
float_power(exponent) → Tensor¶
-
float_power_(exponent) → Tensor¶ In-place version of
float_power()
-
floor() → Tensor¶ See
torch.floor()
-
floor_divide(value) → Tensor¶
-
floor_divide_(value) → Tensor¶ In-place version of
floor_divide()
-
fmod(divisor) → Tensor¶ See
torch.fmod()
-
frac() → Tensor¶ See
torch.frac()
-
gather(dim, index) → Tensor¶ See
torch.gather()
-
gcd(other) → Tensor¶ See
torch.gcd()
-
ge(other) → Tensor¶ See
torch.ge().
-
greater_equal(other) → Tensor¶
-
greater_equal_(other) → Tensor¶ In-place version of
greater_equal().
-
geometric_(p, *, generator=None) → Tensor¶ Fills
selftensor with elements drawn from the geometric distribution:
-
geqrf()¶ See
torch.geqrf()
-
ger(vec2) → Tensor¶ See
torch.ger()
-
get_device() -> Device ordinal (Integer)¶ For CUDA tensors, this function returns the device ordinal of the GPU on which the tensor resides. For CPU tensors, an error is thrown.
Example:
>>> x = torch.randn(3, 4, 5, device='cuda:0') >>> x.get_device() 0 >>> x.cpu().get_device() # RuntimeError: get_device is not implemented for type torch.FloatTensor
-
gt(other) → Tensor¶ See
torch.gt().
-
greater(other) → Tensor¶ See
torch.greater().
-
half(memory_format=torch.preserve_format) → Tensor¶ self.half()is equivalent toself.to(torch.float16). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
hardshrink(lambd=0.5) → Tensor¶
-
heaviside(values) → Tensor¶
-
histc(bins=100, min=0, max=0) → Tensor¶ See
torch.histc()
-
hypot(other) → Tensor¶ See
torch.hypot()
-
i0() → Tensor¶ See
torch.i0()
-
igamma(other) → Tensor¶ See
torch.igamma()
-
igammac(other) → Tensor¶ See
torch.igammac()
-
index_add_(dim, index, tensor) → Tensor¶ Accumulate the elements of
tensorinto theselftensor by adding to the indices in the order given inindex. For example, ifdim == 0andindex[i] == j, then theith row oftensoris added to thejth row ofself.The
dimth dimension oftensormust have the same size as the length ofindex(which must be a vector), and all other dimensions must matchself, or an error will be raised.Note
This operation may behave nondeterministically when given tensors on a CUDA device. See Reproducibility for more information.
- Parameters
Example:
>>> x = torch.ones(5, 3) >>> t = torch.tensor([[1, 2, 3], [4, 5, 6], [7, 8, 9]], dtype=torch.float) >>> index = torch.tensor([0, 4, 2]) >>> x.index_add_(0, index, t) tensor([[ 2., 3., 4.], [ 1., 1., 1.], [ 8., 9., 10.], [ 1., 1., 1.], [ 5., 6., 7.]])
-
index_add(tensor1, dim, index, tensor2) → Tensor¶ Out-of-place version of
torch.Tensor.index_add_(). tensor1 corresponds to self intorch.Tensor.index_add_().
-
index_copy_(dim, index, tensor) → Tensor¶ Copies the elements of
tensorinto theselftensor by selecting the indices in the order given inindex. For example, ifdim == 0andindex[i] == j, then theith row oftensoris copied to thejth row ofself.The
dimth dimension oftensormust have the same size as the length ofindex(which must be a vector), and all other dimensions must matchself, or an error will be raised.Note
If
indexcontains duplicate entries, multiple elements fromtensorwill be copied to the same index ofself. The result is nondeterministic since it depends on which copy occurs last.- Parameters
Example:
>>> x = torch.zeros(5, 3) >>> t = torch.tensor([[1, 2, 3], [4, 5, 6], [7, 8, 9]], dtype=torch.float) >>> index = torch.tensor([0, 4, 2]) >>> x.index_copy_(0, index, t) tensor([[ 1., 2., 3.], [ 0., 0., 0.], [ 7., 8., 9.], [ 0., 0., 0.], [ 4., 5., 6.]])
-
index_copy(tensor1, dim, index, tensor2) → Tensor¶ Out-of-place version of
torch.Tensor.index_copy_(). tensor1 corresponds to self intorch.Tensor.index_copy_().
-
index_fill_(dim, index, val) → Tensor¶ Fills the elements of the
selftensor with valuevalby selecting the indices in the order given inindex.- Parameters
- Example::
>>> x = torch.tensor([[1, 2, 3], [4, 5, 6], [7, 8, 9]], dtype=torch.float) >>> index = torch.tensor([0, 2]) >>> x.index_fill_(1, index, -1) tensor([[-1., 2., -1.], [-1., 5., -1.], [-1., 8., -1.]])
-
index_fill(tensor1, dim, index, value) → Tensor¶ Out-of-place version of
torch.Tensor.index_fill_(). tensor1 corresponds to self intorch.Tensor.index_fill_().
-
index_put_(indices, values, accumulate=False) → Tensor¶ Puts values from the tensor
valuesinto the tensorselfusing the indices specified inindices(which is a tuple of Tensors). The expressiontensor.index_put_(indices, values)is equivalent totensor[indices] = values. Returnsself.If
accumulateisTrue, the elements invaluesare added toself. If accumulate isFalse, the behavior is undefined if indices contain duplicate elements.
-
index_put(tensor1, indices, values, accumulate=False) → Tensor¶ Out-place version of
index_put_(). tensor1 corresponds to self intorch.Tensor.index_put_().
-
index_select(dim, index) → Tensor¶
-
indices() → Tensor Return the indices tensor of a sparse COO tensor.
Warning
Throws an error if
selfis not a sparse COO tensor.See also
Tensor.values().Note
This method can only be called on a coalesced sparse tensor. See
Tensor.coalesce()for details.
-
inner(other) → Tensor¶ See
torch.inner().
-
int(memory_format=torch.preserve_format) → Tensor¶ self.int()is equivalent toself.to(torch.int32). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
int_repr() → Tensor¶ Given a quantized Tensor,
self.int_repr()returns a CPU Tensor with uint8_t as data type that stores the underlying uint8_t values of the given Tensor.
-
inverse() → Tensor¶ See
torch.inverse()
-
isclose(other, rtol=1e-05, atol=1e-08, equal_nan=False) → Tensor¶ See
torch.isclose()
-
isfinite() → Tensor¶ See
torch.isfinite()
-
isinf() → Tensor¶ See
torch.isinf()
-
isposinf() → Tensor¶ See
torch.isposinf()
-
isneginf() → Tensor¶ See
torch.isneginf()
-
isnan() → Tensor¶ See
torch.isnan()
-
is_contiguous(memory_format=torch.contiguous_format) → bool¶ Returns True if
selftensor is contiguous in memory in the order specified by memory format.- Parameters
memory_format (
torch.memory_format, optional) – Specifies memory allocation order. Default:torch.contiguous_format.
-
is_leaf All Tensors that have
requires_gradwhich isFalsewill be leaf Tensors by convention.For Tensors that have
requires_gradwhich isTrue, they will be leaf Tensors if they were created by the user. This means that they are not the result of an operation and sograd_fnis None.Only leaf Tensors will have their
gradpopulated during a call tobackward(). To getgradpopulated for non-leaf Tensors, you can useretain_grad().Example:
>>> a = torch.rand(10, requires_grad=True) >>> a.is_leaf True >>> b = torch.rand(10, requires_grad=True).cuda() >>> b.is_leaf False # b was created by the operation that cast a cpu Tensor into a cuda Tensor >>> c = torch.rand(10, requires_grad=True) + 2 >>> c.is_leaf False # c was created by the addition operation >>> d = torch.rand(10).cuda() >>> d.is_leaf True # d does not require gradients and so has no operation creating it (that is tracked by the autograd engine) >>> e = torch.rand(10).cuda().requires_grad_() >>> e.is_leaf True # e requires gradients and has no operations creating it >>> f = torch.rand(10, requires_grad=True, device="cuda") >>> f.is_leaf True # f requires grad, has no operation creating it
-
is_pinned()¶ Returns true if this tensor resides in pinned memory.
-
is_set_to(tensor) → bool¶ Returns True if both tensors are pointing to the exact same memory (same storage, offset, size and stride).
Checks if tensor is in shared memory.
This is always
Truefor CUDA tensors.
-
is_sparse Is
Trueif the Tensor uses sparse storage layout,Falseotherwise.
-
istft(n_fft, hop_length=None, win_length=None, window=None, center=True, normalized=False, onesided=None, length=None, return_complex=False)[source]¶ See
torch.istft()
-
isreal() → Tensor¶ See
torch.isreal()
-
item() → number¶ Returns the value of this tensor as a standard Python number. This only works for tensors with one element. For other cases, see
tolist().This operation is not differentiable.
Example:
>>> x = torch.tensor([1.0]) >>> x.item() 1.0
-
kthvalue(k, dim=None, keepdim=False)¶ See
torch.kthvalue()
-
lcm(other) → Tensor¶ See
torch.lcm()
-
ldexp(other) → Tensor¶ See
torch.ldexp()
-
le(other) → Tensor¶ See
torch.le().
-
less_equal(other) → Tensor¶ See
torch.less_equal().
-
less_equal_(other) → Tensor¶ In-place version of
less_equal().
-
lerp(end, weight) → Tensor¶ See
torch.lerp()
-
lgamma() → Tensor¶ See
torch.lgamma()
-
log() → Tensor¶ See
torch.log()
-
logdet() → Tensor¶ See
torch.logdet()
-
log10() → Tensor¶ See
torch.log10()
-
log1p() → Tensor¶ See
torch.log1p()
-
log2() → Tensor¶ See
torch.log2()
-
log_normal_(mean=1, std=2, *, generator=None)¶ Fills
selftensor with numbers samples from the log-normal distribution parameterized by the given mean and standard deviation . Note thatmeanandstdare the mean and standard deviation of the underlying normal distribution, and not of the returned distribution:
-
logaddexp(other) → Tensor¶
-
logaddexp2(other) → Tensor¶
-
logsumexp(dim, keepdim=False) → Tensor¶
-
logical_and() → Tensor¶
-
logical_and_() → Tensor¶ In-place version of
logical_and()
-
logical_not() → Tensor¶
-
logical_not_() → Tensor¶ In-place version of
logical_not()
-
logical_or() → Tensor¶
-
logical_or_() → Tensor¶ In-place version of
logical_or()
-
logical_xor() → Tensor¶
-
logical_xor_() → Tensor¶ In-place version of
logical_xor()
-
logit() → Tensor¶ See
torch.logit()
-
long(memory_format=torch.preserve_format) → Tensor¶ self.long()is equivalent toself.to(torch.int64). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
lstsq(A)¶ See
torch.lstsq()
-
lt(other) → Tensor¶ See
torch.lt().
-
less()¶ lt(other) -> Tensor
See
torch.less().
-
lu(pivot=True, get_infos=False)[source]¶ See
torch.lu()
-
lu_solve(LU_data, LU_pivots) → Tensor¶ See
torch.lu_solve()
-
as_subclass(cls) → Tensor¶ Makes a
clsinstance with the same data pointer asself. Changes in the output mirror changes inself, and the output stays attached to the autograd graph.clsmust be a subclass ofTensor.
-
map_(tensor, callable)¶ Applies
callablefor each element inselftensor and the giventensorand stores the results inselftensor.selftensor and the giventensormust be broadcastable.The
callableshould have the signature:def callable(a, b) -> number
-
masked_scatter_(mask, source)¶ Copies elements from
sourceintoselftensor at positions where themaskis True. The shape ofmaskmust be broadcastable with the shape of the underlying tensor. Thesourceshould have at least as many elements as the number of ones inmask- Parameters
mask (BoolTensor) – the boolean mask
source (Tensor) – the tensor to copy from
Note
The
maskoperates on theselftensor, not on the givensourcetensor.
-
masked_scatter(mask, tensor) → Tensor¶ Out-of-place version of
torch.Tensor.masked_scatter_()
-
masked_fill_(mask, value)¶ Fills elements of
selftensor withvaluewheremaskis True. The shape ofmaskmust be broadcastable with the shape of the underlying tensor.- Parameters
mask (BoolTensor) – the boolean mask
value (float) – the value to fill in with
-
masked_fill(mask, value) → Tensor¶ Out-of-place version of
torch.Tensor.masked_fill_()
-
masked_select(mask) → Tensor¶
-
matmul(tensor2) → Tensor¶ See
torch.matmul()
-
matrix_power(n) → Tensor¶
-
matrix_exp() → Tensor¶
-
max(dim=None, keepdim=False)¶ See
torch.max()
-
maximum(other) → Tensor¶ See
torch.maximum()
-
mean(dim=None, keepdim=False)¶ See
torch.mean()
-
median(dim=None, keepdim=False)¶ See
torch.median()
-
nanmedian(dim=None, keepdim=False)¶
-
min(dim=None, keepdim=False)¶ See
torch.min()
-
minimum(other) → Tensor¶ See
torch.minimum()
-
mm(mat2) → Tensor¶ See
torch.mm()
-
smm(mat) → Tensor See
torch.smm()
-
mode(dim=None, keepdim=False)¶ See
torch.mode()
-
movedim(source, destination) → Tensor¶ See
torch.movedim()
-
moveaxis(source, destination) → Tensor¶ See
torch.moveaxis()
-
msort() → Tensor¶ See
torch.msort()
-
mul(value) → Tensor¶ See
torch.mul().
-
multiply(value) → Tensor¶ See
torch.multiply().
-
multiply_(value) → Tensor¶ In-place version of
multiply().
-
multinomial(num_samples, replacement=False, *, generator=None) → Tensor¶
-
mv(vec) → Tensor¶ See
torch.mv()
-
mvlgamma(p) → Tensor¶ See
torch.mvlgamma()
-
mvlgamma_(p) → Tensor¶ In-place version of
mvlgamma()
-
nansum(dim=None, keepdim=False, dtype=None) → Tensor¶ See
torch.nansum()
-
narrow(dimension, start, length) → Tensor¶ See
torch.narrow()Example:
>>> x = torch.tensor([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) >>> x.narrow(0, 0, 2) tensor([[ 1, 2, 3], [ 4, 5, 6]]) >>> x.narrow(1, 1, 2) tensor([[ 2, 3], [ 5, 6], [ 8, 9]])
-
narrow_copy(dimension, start, length) → Tensor¶ Same as
Tensor.narrow()except returning a copy rather than shared storage. This is primarily for sparse tensors, which do not have a shared-storage narrow method. Calling`narrow_copywith`dimemsion > self.sparse_dim()`will return a copy with the relevant dense dimension narrowed, and`self.shape`updated accordingly.
-
nan_to_num(nan=0.0, posinf=None, neginf=None) → Tensor¶ See
torch.nan_to_num().
-
nan_to_num_(nan=0.0, posinf=None, neginf=None) → Tensor¶ In-place version of
nan_to_num().
-
ne(other) → Tensor¶ See
torch.ne().
-
not_equal(other) → Tensor¶ See
torch.not_equal().
-
not_equal_(other) → Tensor¶ In-place version of
not_equal().
-
neg() → Tensor¶ See
torch.neg()
-
negative() → Tensor¶ See
torch.negative()
-
negative_() → Tensor¶ In-place version of
negative()
-
nextafter(other) → Tensor¶
-
nextafter_(other) → Tensor¶ In-place version of
nextafter()
-
nonzero() → LongTensor¶ See
torch.nonzero()
-
norm(p='fro', dim=None, keepdim=False, dtype=None)[source]¶ See
torch.norm()
-
normal_(mean=0, std=1, *, generator=None) → Tensor¶ Fills
selftensor with elements samples from the normal distribution parameterized bymeanandstd.
-
numel() → int¶ See
torch.numel()
-
numpy() → numpy.ndarray¶ Returns
selftensor as a NumPyndarray. This tensor and the returnedndarrayshare the same underlying storage. Changes toselftensor will be reflected in thendarrayand vice versa.
-
orgqr(input2) → Tensor¶ See
torch.orgqr()
-
ormqr(input2, input3, left=True, transpose=False) → Tensor¶ See
torch.ormqr()
-
outer(vec2) → Tensor¶ See
torch.outer().
-
permute(*dims) → Tensor¶ Returns a view of the original tensor with its dimensions permuted.
- Parameters
*dims (int...) – The desired ordering of dimensions
Example
>>> x = torch.randn(2, 3, 5) >>> x.size() torch.Size([2, 3, 5]) >>> x.permute(2, 0, 1).size() torch.Size([5, 2, 3])
-
pin_memory() → Tensor¶ Copies the tensor to pinned memory, if it’s not already pinned.
-
pinverse() → Tensor¶ See
torch.pinverse()
-
polygamma(n) → Tensor¶
-
polygamma_(n) → Tensor¶ In-place version of
polygamma()
-
pow(exponent) → Tensor¶ See
torch.pow()
-
prod(dim=None, keepdim=False, dtype=None) → Tensor¶ See
torch.prod()
-
put_(indices, tensor, accumulate=False) → Tensor¶ Copies the elements from
tensorinto the positions specified by indices. For the purpose of indexing, theselftensor is treated as if it were a 1-D tensor.If
accumulateisTrue, the elements intensorare added toself. If accumulate isFalse, the behavior is undefined if indices contain duplicate elements.- Parameters
Example:
>>> src = torch.tensor([[4, 3, 5], ... [6, 7, 8]]) >>> src.put_(torch.tensor([1, 3]), torch.tensor([9, 10])) tensor([[ 4, 9, 5], [ 10, 7, 8]])
-
qr(some=True)¶ See
torch.qr()
-
qscheme() → torch.qscheme¶ Returns the quantization scheme of a given QTensor.
-
quantile(q, dim=None, keepdim=False) → Tensor¶ See
torch.quantile()
-
nanquantile(q, dim=None, keepdim=False) → Tensor¶
-
q_scale() → float¶ Given a Tensor quantized by linear(affine) quantization, returns the scale of the underlying quantizer().
-
q_zero_point() → int¶ Given a Tensor quantized by linear(affine) quantization, returns the zero_point of the underlying quantizer().
-
q_per_channel_scales() → Tensor¶ Given a Tensor quantized by linear (affine) per-channel quantization, returns a Tensor of scales of the underlying quantizer. It has the number of elements that matches the corresponding dimensions (from q_per_channel_axis) of the tensor.
-
q_per_channel_zero_points() → Tensor¶ Given a Tensor quantized by linear (affine) per-channel quantization, returns a tensor of zero_points of the underlying quantizer. It has the number of elements that matches the corresponding dimensions (from q_per_channel_axis) of the tensor.
-
q_per_channel_axis() → int¶ Given a Tensor quantized by linear (affine) per-channel quantization, returns the index of dimension on which per-channel quantization is applied.
-
rad2deg() → Tensor¶ See
torch.rad2deg()
-
random_(from=0, to=None, *, generator=None) → Tensor¶ Fills
selftensor with numbers sampled from the discrete uniform distribution over[from, to - 1]. If not specified, the values are usually only bounded byselftensor’s data type. However, for floating point types, if unspecified, range will be[0, 2^mantissa]to ensure that every value is representable. For example, torch.tensor(1, dtype=torch.double).random_() will be uniform in[0, 2^53].
-
ravel(input) → Tensor¶ see
torch.ravel()
-
reciprocal() → Tensor¶
-
reciprocal_() → Tensor¶ In-place version of
reciprocal()
-
record_stream(stream)¶ Ensures that the tensor memory is not reused for another tensor until all current work queued on
streamare complete.Note
The caching allocator is aware of only the stream where a tensor was allocated. Due to the awareness, it already correctly manages the life cycle of tensors on only one stream. But if a tensor is used on a stream different from the stream of origin, the allocator might reuse the memory unexpectedly. Calling this method lets the allocator know which streams have used the tensor.
-
register_hook(hook)[source] Registers a backward hook.
The hook will be called every time a gradient with respect to the Tensor is computed. The hook should have the following signature:
hook(grad) -> Tensor or None
The hook should not modify its argument, but it can optionally return a new gradient which will be used in place of
grad.This function returns a handle with a method
handle.remove()that removes the hook from the module.Example:
>>> v = torch.tensor([0., 0., 0.], requires_grad=True) >>> h = v.register_hook(lambda grad: grad * 2) # double the gradient >>> v.backward(torch.tensor([1., 2., 3.])) >>> v.grad 2 4 6 [torch.FloatTensor of size (3,)] >>> h.remove() # removes the hook
-
remainder(divisor) → Tensor¶
-
remainder_(divisor) → Tensor¶ In-place version of
remainder()
-
renorm(p, dim, maxnorm) → Tensor¶ See
torch.renorm()
-
repeat(*sizes) → Tensor¶ Repeats this tensor along the specified dimensions.
Unlike
expand(), this function copies the tensor’s data.Warning
repeat()behaves differently from numpy.repeat, but is more similar to numpy.tile. For the operator similar to numpy.repeat, seetorch.repeat_interleave().- Parameters
sizes (torch.Size or int...) – The number of times to repeat this tensor along each dimension
Example:
>>> x = torch.tensor([1, 2, 3]) >>> x.repeat(4, 2) tensor([[ 1, 2, 3, 1, 2, 3], [ 1, 2, 3, 1, 2, 3], [ 1, 2, 3, 1, 2, 3], [ 1, 2, 3, 1, 2, 3]]) >>> x.repeat(4, 2, 1).size() torch.Size([4, 2, 3])
-
repeat_interleave(repeats, dim=None) → Tensor¶
-
requires_grad Is
Trueif gradients need to be computed for this Tensor,Falseotherwise.
-
requires_grad_(requires_grad=True) → Tensor¶ Change if autograd should record operations on this tensor: sets this tensor’s
requires_gradattribute in-place. Returns this tensor.requires_grad_()’s main use case is to tell autograd to begin recording operations on a Tensortensor. Iftensorhasrequires_grad=False(because it was obtained through a DataLoader, or required preprocessing or initialization),tensor.requires_grad_()makes it so that autograd will begin to record operations ontensor.- Parameters
requires_grad (bool) – If autograd should record operations on this tensor. Default:
True.
Example:
>>> # Let's say we want to preprocess some saved weights and use >>> # the result as new weights. >>> saved_weights = [0.1, 0.2, 0.3, 0.25] >>> loaded_weights = torch.tensor(saved_weights) >>> weights = preprocess(loaded_weights) # some function >>> weights tensor([-0.5503, 0.4926, -2.1158, -0.8303]) >>> # Now, start to record operations done to weights >>> weights.requires_grad_() >>> out = weights.pow(2).sum() >>> out.backward() >>> weights.grad tensor([-1.1007, 0.9853, -4.2316, -1.6606])
-
reshape(*shape) → Tensor¶ Returns a tensor with the same data and number of elements as
selfbut with the specified shape. This method returns a view ifshapeis compatible with the current shape. Seetorch.Tensor.view()on when it is possible to return a view.See
torch.reshape()- Parameters
shape (tuple of python:ints or int...) – the desired shape
-
reshape_as(other) → Tensor¶ Returns this tensor as the same shape as
other.self.reshape_as(other)is equivalent toself.reshape(other.sizes()). This method returns a view ifother.sizes()is compatible with the current shape. Seetorch.Tensor.view()on when it is possible to return a view.Please see
reshape()for more information aboutreshape.- Parameters
other (
torch.Tensor) – The result tensor has the same shape asother.
-
resize_(*sizes, memory_format=torch.contiguous_format) → Tensor¶ Resizes
selftensor to the specified size. If the number of elements is larger than the current storage size, then the underlying storage is resized to fit the new number of elements. If the number of elements is smaller, the underlying storage is not changed. Existing elements are preserved but any new memory is uninitialized.Warning
This is a low-level method. The storage is reinterpreted as C-contiguous, ignoring the current strides (unless the target size equals the current size, in which case the tensor is left unchanged). For most purposes, you will instead want to use
view(), which checks for contiguity, orreshape(), which copies data if needed. To change the size in-place with custom strides, seeset_().- Parameters
sizes (torch.Size or int...) – the desired size
memory_format (
torch.memory_format, optional) – the desired memory format of Tensor. Default:torch.contiguous_format. Note that memory format ofselfis going to be unaffected ifself.size()matchessizes.
Example:
>>> x = torch.tensor([[1, 2], [3, 4], [5, 6]]) >>> x.resize_(2, 2) tensor([[ 1, 2], [ 3, 4]])
-
resize_as_(tensor, memory_format=torch.contiguous_format) → Tensor¶ Resizes the
selftensor to be the same size as the specifiedtensor. This is equivalent toself.resize_(tensor.size()).- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of Tensor. Default:torch.contiguous_format. Note that memory format ofselfis going to be unaffected ifself.size()matchestensor.size().
-
retain_grad()[source] Enables .grad attribute for non-leaf Tensors.
-
roll(shifts, dims) → Tensor¶ See
torch.roll()
-
rot90(k, dims) → Tensor¶ See
torch.rot90()
-
round() → Tensor¶ See
torch.round()
-
rsqrt() → Tensor¶ See
torch.rsqrt()
-
scatter(dim, index, src) → Tensor¶ Out-of-place version of
torch.Tensor.scatter_()
-
scatter_(dim, index, src, reduce=None) → Tensor¶ Writes all values from the tensor
srcintoselfat the indices specified in theindextensor. For each value insrc, its output index is specified by its index insrcfordimension != dimand by the corresponding value inindexfordimension = dim.For a 3-D tensor,
selfis updated as:self[index[i][j][k]][j][k] = src[i][j][k] # if dim == 0 self[i][index[i][j][k]][k] = src[i][j][k] # if dim == 1 self[i][j][index[i][j][k]] = src[i][j][k] # if dim == 2
This is the reverse operation of the manner described in
gather().self,indexandsrc(if it is a Tensor) should all have the same number of dimensions. It is also required thatindex.size(d) <= src.size(d)for all dimensionsd, and thatindex.size(d) <= self.size(d)for all dimensionsd != dim. Note thatindexandsrcdo not broadcast.Moreover, as for
gather(), the values ofindexmust be between0andself.size(dim) - 1inclusive.Warning
When indices are not unique, the behavior is non-deterministic (one of the values from
srcwill be picked arbitrarily) and the gradient will be incorrect (it will be propagated to all locations in the source that correspond to the same index)!Note
The backward pass is implemented only for
src.shape == index.shape.Additionally accepts an optional
reduceargument that allows specification of an optional reduction operation, which is applied to all values in the tensorsrcintoselfat the indicies specified in theindex. For each value insrc, the reduction operation is applied to an index inselfwhich is specified by its index insrcfordimension != dimand by the corresponding value inindexfordimension = dim.Given a 3-D tensor and reduction using the multiplication operation,
selfis updated as:self[index[i][j][k]][j][k] *= src[i][j][k] # if dim == 0 self[i][index[i][j][k]][k] *= src[i][j][k] # if dim == 1 self[i][j][index[i][j][k]] *= src[i][j][k] # if dim == 2
Reducing with the addition operation is the same as using
scatter_add_().- Parameters
Example:
>>> src = torch.arange(1, 11).reshape((2, 5)) >>> src tensor([[ 1, 2, 3, 4, 5], [ 6, 7, 8, 9, 10]]) >>> index = torch.tensor([[0, 1, 2, 0]]) >>> torch.zeros(3, 5, dtype=src.dtype).scatter_(0, index, src) tensor([[1, 0, 0, 4, 0], [0, 2, 0, 0, 0], [0, 0, 3, 0, 0]]) >>> index = torch.tensor([[0, 1, 2], [0, 1, 4]]) >>> torch.zeros(3, 5, dtype=src.dtype).scatter_(1, index, src) tensor([[1, 2, 3, 0, 0], [6, 7, 0, 0, 8], [0, 0, 0, 0, 0]]) >>> torch.full((2, 4), 2.).scatter_(1, torch.tensor([[2], [3]]), ... 1.23, reduce='multiply') tensor([[2.0000, 2.0000, 2.4600, 2.0000], [2.0000, 2.0000, 2.0000, 2.4600]]) >>> torch.full((2, 4), 2.).scatter_(1, torch.tensor([[2], [3]]), ... 1.23, reduce='add') tensor([[2.0000, 2.0000, 3.2300, 2.0000], [2.0000, 2.0000, 2.0000, 3.2300]])
-
scatter_add_(dim, index, src) → Tensor¶ Adds all values from the tensor
otherintoselfat the indices specified in theindextensor in a similar fashion asscatter_(). For each value insrc, it is added to an index inselfwhich is specified by its index insrcfordimension != dimand by the corresponding value inindexfordimension = dim.For a 3-D tensor,
selfis updated as:self[index[i][j][k]][j][k] += src[i][j][k] # if dim == 0 self[i][index[i][j][k]][k] += src[i][j][k] # if dim == 1 self[i][j][index[i][j][k]] += src[i][j][k] # if dim == 2
self,indexandsrcshould have same number of dimensions. It is also required thatindex.size(d) <= src.size(d)for all dimensionsd, and thatindex.size(d) <= self.size(d)for all dimensionsd != dim. Note thatindexandsrcdo not broadcast.Note
This operation may behave nondeterministically when given tensors on a CUDA device. See Reproducibility for more information.
Note
The backward pass is implemented only for
src.shape == index.shape.- Parameters
Example:
>>> src = torch.ones((2, 5)) >>> index = torch.tensor([[0, 1, 2, 0, 0]]) >>> torch.zeros(3, 5, dtype=src.dtype).scatter_add_(0, index, src) tensor([[1., 0., 0., 1., 1.], [0., 1., 0., 0., 0.], [0., 0., 1., 0., 0.]]) >>> index = torch.tensor([[0, 1, 2, 0, 0], [0, 1, 2, 2, 2]]) >>> torch.zeros(3, 5, dtype=src.dtype).scatter_add_(0, index, src) tensor([[2., 0., 0., 1., 1.], [0., 2., 0., 0., 0.], [0., 0., 2., 1., 1.]])
-
scatter_add(dim, index, src) → Tensor¶ Out-of-place version of
torch.Tensor.scatter_add_()
-
select(dim, index) → Tensor¶ Slices the
selftensor along the selected dimension at the given index. This function returns a view of the original tensor with the given dimension removed.Note
select()is equivalent to slicing. For example,tensor.select(0, index)is equivalent totensor[index]andtensor.select(2, index)is equivalent totensor[:,:,index].
-
set_(source=None, storage_offset=0, size=None, stride=None) → Tensor¶ Sets the underlying storage, size, and strides. If
sourceis a tensor,selftensor will share the same storage and have the same size and strides assource. Changes to elements in one tensor will be reflected in the other.If
sourceis aStorage, the method sets the underlying storage, offset, size, and stride.
Moves the underlying storage to shared memory.
This is a no-op if the underlying storage is already in shared memory and for CUDA tensors. Tensors in shared memory cannot be resized.
-
short(memory_format=torch.preserve_format) → Tensor¶ self.short()is equivalent toself.to(torch.int16). Seeto().- Parameters
memory_format (
torch.memory_format, optional) – the desired memory format of returned Tensor. Default:torch.preserve_format.
-
sigmoid() → Tensor¶ See
torch.sigmoid()
-
sign() → Tensor¶ See
torch.sign()
-
signbit() → Tensor¶ See
torch.signbit()
-
sgn() → Tensor¶ See
torch.sgn()
-
sin() → Tensor¶ See
torch.sin()
-
sinc() → Tensor¶ See
torch.sinc()
-
sinh() → Tensor¶ See
torch.sinh()
-
asinh() → Tensor¶ See
torch.asinh()
-
arcsinh() → Tensor¶ See
torch.arcsinh()
-
size() → torch.Size¶ Returns the size of the
selftensor. The returned value is a subclass oftuple.Example:
>>> torch.empty(3, 4, 5).size() torch.Size([3, 4, 5])
-
slogdet()¶ See
torch.slogdet()
-
solve(A) → Tensor, Tensor¶ See
torch.solve()
-
sort(dim=- 1, descending=False)¶ See
torch.sort()
-
split(split_size, dim=0)[source]¶ See
torch.split()
-
sparse_mask(mask) → Tensor Returns a new sparse tensor with values from a strided tensor
selffiltered by the indices of the sparse tensormask. The values ofmasksparse tensor are ignored.selfandmasktensors must have the same shape.Note
The returned sparse tensor has the same indices as the sparse tensor
mask, even when the corresponding values inselfare zeros.- Parameters
mask (Tensor) – a sparse tensor whose indices are used as a filter
Example:
>>> nse = 5 >>> dims = (5, 5, 2, 2) >>> I = torch.cat([torch.randint(0, dims[0], size=(nse,)), ... torch.randint(0, dims[1], size=(nse,))], 0).reshape(2, nse) >>> V = torch.randn(nse, dims[2], dims[3]) >>> S = torch.sparse_coo_tensor(I, V, dims).coalesce() >>> D = torch.randn(dims) >>> D.sparse_mask(S) tensor(indices=tensor([[0, 0, 0, 2], [0, 1, 4, 3]]), values=tensor([[[ 1.6550, 0.2397], [-0.1611, -0.0779]], [[ 0.2326, -1.0558], [ 1.4711, 1.9678]], [[-0.5138, -0.0411], [ 1.9417, 0.5158]], [[ 0.0793, 0.0036], [-0.2569, -0.1055]]]), size=(5, 5, 2, 2), nnz=4, layout=torch.sparse_coo)
-
sparse_dim() → int Return the number of sparse dimensions in a sparse tensor
self.Warning
Throws an error if
selfis not a sparse tensor.See also
Tensor.dense_dim()and hybrid tensors.
-
sqrt() → Tensor¶ See
torch.sqrt()
-
square() → Tensor¶ See
torch.square()
-
squeeze(dim=None) → Tensor¶ See
torch.squeeze()
-
std(dim=None, unbiased=True, keepdim=False) → Tensor¶ See
torch.std()
-
stft(n_fft, hop_length=None, win_length=None, window=None, center=True, pad_mode='reflect', normalized=False, onesided=None, return_complex=None)[source]¶ See
torch.stft()Warning
This function changed signature at version 0.4.1. Calling with the previous signature may cause error or return incorrect result.
-
storage() → torch.Storage¶ Returns the underlying storage.
-
storage_offset() → int¶ Returns
selftensor’s offset in the underlying storage in terms of number of storage elements (not bytes).Example:
>>> x = torch.tensor([1, 2, 3, 4, 5]) >>> x.storage_offset() 0 >>> x[3:].storage_offset() 3
-
stride(dim) → tuple or int¶ Returns the stride of
selftensor.Stride is the jump necessary to go from one element to the next one in the specified dimension
dim. A tuple of all strides is returned when no argument is passed in. Otherwise, an integer value is returned as the stride in the particular dimensiondim.- Parameters
dim (int, optional) – the desired dimension in which stride is required
Example:
>>> x = torch.tensor([[1, 2, 3, 4, 5], [6, 7, 8, 9, 10]]) >>> x.stride() (5, 1) >>> x.stride(0) 5 >>> x.stride(-1) 1
-
sub(other, *, alpha=1) → Tensor¶ See
torch.sub().
-
subtract(other, *, alpha=1) → Tensor¶ See
torch.subtract().
-
subtract_(other, *, alpha=1) → Tensor¶ In-place version of
subtract().
-
sum(dim=None, keepdim=False, dtype=None) → Tensor¶ See
torch.sum()
-
sum_to_size(*size) → Tensor¶ Sum
thistensor tosize.sizemust be broadcastable tothistensor size.- Parameters
size (int...) – a sequence of integers defining the shape of the output tensor.
-
svd(some=True, compute_uv=True)¶ See
torch.svd()
-
swapaxes(axis0, axis1) → Tensor¶ See
torch.swapaxes()
-
swapdims(dim0, dim1) → Tensor¶ See
torch.swapdims()
-
symeig(eigenvectors=False, upper=True)¶ See
torch.symeig()
-
tensor_split(indices_or_sections, dim=0) → List of Tensors¶
-
tile(*reps) → Tensor¶ See
torch.tile()
-
to(*args, **kwargs) → Tensor¶ Performs Tensor dtype and/or device conversion. A
torch.dtypeandtorch.deviceare inferred from the arguments ofself.to(*args, **kwargs).Note
If the
selfTensor already has the correcttorch.dtypeandtorch.device, thenselfis returned. Otherwise, the returned tensor is a copy ofselfwith the desiredtorch.dtypeandtorch.device.Here are the ways to call
to:-
to(dtype, non_blocking=False, copy=False, memory_format=torch.preserve_format) → Tensor¶ Returns a Tensor with the specified
dtype- Args:
memory_format (
torch.memory_format, optional): the desired memory format of returned Tensor. Default:torch.preserve_format.
-
to(device=None, dtype=None, non_blocking=False, copy=False, memory_format=torch.preserve_format) → Tensor¶ Returns a Tensor with the specified
deviceand (optional)dtype. IfdtypeisNoneit is inferred to beself.dtype. Whennon_blocking, tries to convert asynchronously with respect to the host if possible, e.g., converting a CPU Tensor with pinned memory to a CUDA Tensor. Whencopyis set, a new Tensor is created even when the Tensor already matches the desired conversion.- Args:
memory_format (
torch.memory_format, optional): the desired memory format of returned Tensor. Default:torch.preserve_format.
-
to(other, non_blocking=False, copy=False) → Tensor¶ Returns a Tensor with same
torch.dtypeandtorch.deviceas the Tensorother. Whennon_blocking, tries to convert asynchronously with respect to the host if possible, e.g., converting a CPU Tensor with pinned memory to a CUDA Tensor. Whencopyis set, a new Tensor is created even when the Tensor already matches the desired conversion.
Example:
>>> tensor = torch.randn(2, 2) # Initially dtype=float32, device=cpu >>> tensor.to(torch.float64) tensor([[-0.5044, 0.0005], [ 0.3310, -0.0584]], dtype=torch.float64) >>> cuda0 = torch.device('cuda:0') >>> tensor.to(cuda0) tensor([[-0.5044, 0.0005], [ 0.3310, -0.0584]], device='cuda:0') >>> tensor.to(cuda0, dtype=torch.float64) tensor([[-0.5044, 0.0005], [ 0.3310, -0.0584]], dtype=torch.float64, device='cuda:0') >>> other = torch.randn((), dtype=torch.float64, device=cuda0) >>> tensor.to(other, non_blocking=True) tensor([[-0.5044, 0.0005], [ 0.3310, -0.0584]], dtype=torch.float64, device='cuda:0')
-
-
to_mkldnn() → Tensor¶ Returns a copy of the tensor in
torch.mkldnnlayout.
-
take(indices) → Tensor¶ See
torch.take()
-
tan() → Tensor¶ See
torch.tan()
-
tanh() → Tensor¶ See
torch.tanh()
-
atanh() → Tensor¶ See
torch.atanh()
-
arctanh() → Tensor¶ See
torch.arctanh()
-
tolist() → list or number¶ Returns the tensor as a (nested) list. For scalars, a standard Python number is returned, just like with
item(). Tensors are automatically moved to the CPU first if necessary.This operation is not differentiable.
Examples:
>>> a = torch.randn(2, 2) >>> a.tolist() [[0.012766935862600803, 0.5415473580360413], [-0.08909505605697632, 0.7729271650314331]] >>> a[0,0].tolist() 0.012766935862600803
-
topk(k, dim=None, largest=True, sorted=True)¶ See
torch.topk()
-
to_sparse(sparseDims) → Tensor Returns a sparse copy of the tensor. PyTorch supports sparse tensors in coordinate format.
- Parameters
sparseDims (int, optional) – the number of sparse dimensions to include in the new sparse tensor
Example:
>>> d = torch.tensor([[0, 0, 0], [9, 0, 10], [0, 0, 0]]) >>> d tensor([[ 0, 0, 0], [ 9, 0, 10], [ 0, 0, 0]]) >>> d.to_sparse() tensor(indices=tensor([[1, 1], [0, 2]]), values=tensor([ 9, 10]), size=(3, 3), nnz=2, layout=torch.sparse_coo) >>> d.to_sparse(1) tensor(indices=tensor([[1]]), values=tensor([[ 9, 0, 10]]), size=(3, 3), nnz=1, layout=torch.sparse_coo)
-
trace() → Tensor¶ See
torch.trace()
-
transpose(dim0, dim1) → Tensor¶
-
transpose_(dim0, dim1) → Tensor¶ In-place version of
transpose()
-
triangular_solve(A, upper=True, transpose=False, unitriangular=False)¶
-
tril(k=0) → Tensor¶ See
torch.tril()
-
triu(k=0) → Tensor¶ See
torch.triu()
-
true_divide(value) → Tensor¶
-
true_divide_(value) → Tensor¶ In-place version of
true_divide_()
-
trunc() → Tensor¶ See
torch.trunc()
-
type(dtype=None, non_blocking=False, **kwargs) → str or Tensor¶ Returns the type if dtype is not provided, else casts this object to the specified type.
If this is already of the correct type, no copy is performed and the original object is returned.
- Parameters
dtype (type or string) – The desired type
non_blocking (bool) – If
True, and the source is in pinned memory and destination is on the GPU or vice versa, the copy is performed asynchronously with respect to the host. Otherwise, the argument has no effect.**kwargs – For compatibility, may contain the key
asyncin place of thenon_blockingargument. Theasyncarg is deprecated.
-
type_as(tensor) → Tensor¶ Returns this tensor cast to the type of the given tensor.
This is a no-op if the tensor is already of the correct type. This is equivalent to
self.type(tensor.type())- Parameters
tensor (Tensor) – the tensor which has the desired type
-
unbind(dim=0) → seq¶ See
torch.unbind()
-
unfold(dimension, size, step) → Tensor¶ Returns a view of the original tensor which contains all slices of size
sizefromselftensor in the dimensiondimension.Step between two slices is given by
step.If sizedim is the size of dimension
dimensionforself, the size of dimensiondimensionin the returned tensor will be (sizedim - size) / step + 1.An additional dimension of size
sizeis appended in the returned tensor.- Parameters
Example:
>>> x = torch.arange(1., 8) >>> x tensor([ 1., 2., 3., 4., 5., 6., 7.]) >>> x.unfold(0, 2, 1) tensor([[ 1., 2.], [ 2., 3.], [ 3., 4.], [ 4., 5.], [ 5., 6.], [ 6., 7.]]) >>> x.unfold(0, 2, 2) tensor([[ 1., 2.], [ 3., 4.], [ 5., 6.]])
-
uniform_(from=0, to=1) → Tensor¶ Fills
selftensor with numbers sampled from the continuous uniform distribution:
-
unique(sorted=True, return_inverse=False, return_counts=False, dim=None)[source]¶ Returns the unique elements of the input tensor.
See
torch.unique()
-
unique_consecutive(return_inverse=False, return_counts=False, dim=None)[source]¶ Eliminates all but the first element from every consecutive group of equivalent elements.
-
unsqueeze(dim) → Tensor¶
-
unsqueeze_(dim) → Tensor¶ In-place version of
unsqueeze()
-
values() → Tensor Return the values tensor of a sparse COO tensor.
Warning
Throws an error if
selfis not a sparse COO tensor.See also
Tensor.indices().Note
This method can only be called on a coalesced sparse tensor. See
Tensor.coalesce()for details.
-
var(dim=None, unbiased=True, keepdim=False) → Tensor¶ See
torch.var()
-
vdot(other) → Tensor¶ See
torch.vdot()
-
view(*shape) → Tensor¶ Returns a new tensor with the same data as the
selftensor but of a differentshape.The returned tensor shares the same data and must have the same number of elements, but may have a different size. For a tensor to be viewed, the new view size must be compatible with its original size and stride, i.e., each new view dimension must either be a subspace of an original dimension, or only span across original dimensions that satisfy the following contiguity-like condition that ,
Otherwise, it will not be possible to view
selftensor asshapewithout copying it (e.g., viacontiguous()). When it is unclear whether aview()can be performed, it is advisable to usereshape(), which returns a view if the shapes are compatible, and copies (equivalent to callingcontiguous()) otherwise.- Parameters
shape (torch.Size or int...) – the desired size
Example:
>>> x = torch.randn(4, 4) >>> x.size() torch.Size([4, 4]) >>> y = x.view(16) >>> y.size() torch.Size([16]) >>> z = x.view(-1, 8) # the size -1 is inferred from other dimensions >>> z.size() torch.Size([2, 8]) >>> a = torch.randn(1, 2, 3, 4) >>> a.size() torch.Size([1, 2, 3, 4]) >>> b = a.transpose(1, 2) # Swaps 2nd and 3rd dimension >>> b.size() torch.Size([1, 3, 2, 4]) >>> c = a.view(1, 3, 2, 4) # Does not change tensor layout in memory >>> c.size() torch.Size([1, 3, 2, 4]) >>> torch.equal(b, c) False
-
view(dtype) → Tensor¶
Returns a new tensor with the same data as the
selftensor but of a differentdtype.dtypemust have the same number of bytes per element asself’s dtype.Warning
This overload is not supported by TorchScript, and using it in a Torchscript program will cause undefined behavior.
- Parameters
dtype (
torch.dtype) – the desired dtype
Example:
>>> x = torch.randn(4, 4) >>> x tensor([[ 0.9482, -0.0310, 1.4999, -0.5316], [-0.1520, 0.7472, 0.5617, -0.8649], [-2.4724, -0.0334, -0.2976, -0.8499], [-0.2109, 1.9913, -0.9607, -0.6123]]) >>> x.dtype torch.float32 >>> y = x.view(torch.int32) >>> y tensor([[ 1064483442, -1124191867, 1069546515, -1089989247], [-1105482831, 1061112040, 1057999968, -1084397505], [-1071760287, -1123489973, -1097310419, -1084649136], [-1101533110, 1073668768, -1082790149, -1088634448]], dtype=torch.int32) >>> y[0, 0] = 1000000000 >>> x tensor([[ 0.0047, -0.0310, 1.4999, -0.5316], [-0.1520, 0.7472, 0.5617, -0.8649], [-2.4724, -0.0334, -0.2976, -0.8499], [-0.2109, 1.9913, -0.9607, -0.6123]]) >>> x.view(torch.int16) Traceback (most recent call last): File "<stdin>", line 1, in <module> RuntimeError: Viewing a tensor as a new dtype with a different number of bytes per element is not supported.
-
view_as(other) → Tensor¶ View this tensor as the same size as
other.self.view_as(other)is equivalent toself.view(other.size()).Please see
view()for more information aboutview.- Parameters
other (
torch.Tensor) – The result tensor has the same size asother.
-
where(condition, y) → Tensor¶ self.where(condition, y)is equivalent totorch.where(condition, self, y). Seetorch.where()
-
xlogy(other) → Tensor¶ See
torch.xlogy()
-
zero_() → Tensor¶ Fills
selftensor with zeros.