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https://github.com/pytorch/pytorch.git
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fb40e58f24
Summary: This removes the deprecated `tensor.new_*` constructors (see #16770) from `torch.distributions` module. Pull Request resolved: https://github.com/pytorch/pytorch/pull/19979 Differential Revision: D15195618 Pulled By: soumith fbshipit-source-id: 46b519bfd32017265e90bd5c53f12cfe4a138021
106 lines
3.7 KiB
Python
106 lines
3.7 KiB
Python
from functools import update_wrapper
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from numbers import Number
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import torch
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import torch.nn.functional as F
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def broadcast_all(*values):
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r"""
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Given a list of values (possibly containing numbers), returns a list where each
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value is broadcasted based on the following rules:
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- `torch.*Tensor` instances are broadcasted as per :ref:`_broadcasting-semantics`.
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- numbers.Number instances (scalars) are upcast to tensors having
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the same size and type as the first tensor passed to `values`. If all the
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values are scalars, then they are upcasted to scalar Tensors.
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Args:
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values (list of `numbers.Number` or `torch.*Tensor`)
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Raises:
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ValueError: if any of the values is not a `numbers.Number` or
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`torch.*Tensor` instance
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"""
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if not all(torch.is_tensor(v) or isinstance(v, Number) for v in values):
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raise ValueError('Input arguments must all be instances of numbers.Number or torch.tensor.')
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if not all(map(torch.is_tensor, values)):
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options = dict(dtype=torch.get_default_dtype())
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for value in values:
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if torch.is_tensor(value):
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options = dict(dtype=value.dtype, device=value.device)
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break
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values = [v if torch.is_tensor(v) else torch.tensor(v, **options)
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for v in values]
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return torch.broadcast_tensors(*values)
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def _standard_normal(shape, dtype, device):
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if torch._C._get_tracing_state():
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# [JIT WORKAROUND] lack of support for .normal_()
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return torch.normal(torch.zeros(shape, dtype=dtype, device=device),
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torch.ones(shape, dtype=dtype, device=device))
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return torch.empty(shape, dtype=dtype, device=device).normal_()
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def _sum_rightmost(value, dim):
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r"""
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Sum out ``dim`` many rightmost dimensions of a given tensor.
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Args:
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value (Tensor): A tensor of ``.dim()`` at least ``dim``.
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dim (int): The number of rightmost dims to sum out.
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"""
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if dim == 0:
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return value
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required_shape = value.shape[:-dim] + (-1,)
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return value.reshape(required_shape).sum(-1)
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def logits_to_probs(logits, is_binary=False):
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r"""
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Converts a tensor of logits into probabilities. Note that for the
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binary case, each value denotes log odds, whereas for the
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multi-dimensional case, the values along the last dimension denote
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the log probabilities (possibly unnormalized) of the events.
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"""
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if is_binary:
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return torch.sigmoid(logits)
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return F.softmax(logits, dim=-1)
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def clamp_probs(probs):
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eps = torch.finfo(probs.dtype).eps
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return probs.clamp(min=eps, max=1 - eps)
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def probs_to_logits(probs, is_binary=False):
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r"""
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Converts a tensor of probabilities into logits. For the binary case,
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this denotes the probability of occurrence of the event indexed by `1`.
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For the multi-dimensional case, the values along the last dimension
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denote the probabilities of occurrence of each of the events.
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"""
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ps_clamped = clamp_probs(probs)
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if is_binary:
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return torch.log(ps_clamped) - torch.log1p(-ps_clamped)
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return torch.log(ps_clamped)
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class lazy_property(object):
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r"""
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Used as a decorator for lazy loading of class attributes. This uses a
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non-data descriptor that calls the wrapped method to compute the property on
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first call; thereafter replacing the wrapped method into an instance
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attribute.
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"""
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def __init__(self, wrapped):
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self.wrapped = wrapped
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update_wrapper(self, wrapped)
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def __get__(self, instance, obj_type=None):
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if instance is None:
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return self
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with torch.enable_grad():
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value = self.wrapped(instance)
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setattr(instance, self.wrapped.__name__, value)
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return value
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