pytorch/torch/nn/modules/distance.py
David Riazati 10c4b98ade Remove weak script (#22212)
Summary:
* Deletes all weak script decorators / associated data structures / methods
   * In order to keep supporting the standard library in script, this enables recursive script on any function defined in `torch.nn`
   * Most changes in `torch/nn` are the result of `ag -Q "weak" torch/nn/ -l | xargs sed -i '/weak/d'`, only `rnn.py` needed manual editing to use the `ignore` and `export` to continue supporting the overloaded `forward` methods
* `Sequential`/`ModuleList` no longer need to be added to constants since they are compiled on demand

This should also fix https://github.com/pytorch/pytorch/issues/22212
Pull Request resolved: https://github.com/pytorch/pytorch/pull/22212

Differential Revision: D15988346

Pulled By: driazati

fbshipit-source-id: af223e3ad0580be895377312949997a70e988e4f
2019-07-03 17:28:25 -07:00

69 lines
2.4 KiB
Python

from .module import Module
from .. import functional as F
class PairwiseDistance(Module):
r"""
Computes the batchwise pairwise distance between vectors :math:`v_1`, :math:`v_2` using the p-norm:
.. math ::
\Vert x \Vert _p = \left( \sum_{i=1}^n \vert x_i \vert ^ p \right) ^ {1/p}.
Args:
p (real): the norm degree. Default: 2
eps (float, optional): Small value to avoid division by zero.
Default: 1e-6
keepdim (bool, optional): Determines whether or not to keep the vector dimension.
Default: False
Shape:
- Input1: :math:`(N, D)` where `D = vector dimension`
- Input2: :math:`(N, D)`, same shape as the Input1
- Output: :math:`(N)`. If :attr:`keepdim` is ``True``, then :math:`(N, 1)`.
Examples::
>>> pdist = nn.PairwiseDistance(p=2)
>>> input1 = torch.randn(100, 128)
>>> input2 = torch.randn(100, 128)
>>> output = pdist(input1, input2)
"""
__constants__ = ['norm', 'eps', 'keepdim']
def __init__(self, p=2., eps=1e-6, keepdim=False):
super(PairwiseDistance, self).__init__()
self.norm = p
self.eps = eps
self.keepdim = keepdim
def forward(self, x1, x2):
return F.pairwise_distance(x1, x2, self.norm, self.eps, self.keepdim)
class CosineSimilarity(Module):
r"""Returns cosine similarity between :math:`x_1` and :math:`x_2`, computed along dim.
.. math ::
\text{similarity} = \dfrac{x_1 \cdot x_2}{\max(\Vert x_1 \Vert _2 \cdot \Vert x_2 \Vert _2, \epsilon)}.
Args:
dim (int, optional): Dimension where cosine similarity is computed. Default: 1
eps (float, optional): Small value to avoid division by zero.
Default: 1e-8
Shape:
- Input1: :math:`(\ast_1, D, \ast_2)` where D is at position `dim`
- Input2: :math:`(\ast_1, D, \ast_2)`, same shape as the Input1
- Output: :math:`(\ast_1, \ast_2)`
Examples::
>>> input1 = torch.randn(100, 128)
>>> input2 = torch.randn(100, 128)
>>> cos = nn.CosineSimilarity(dim=1, eps=1e-6)
>>> output = cos(input1, input2)
"""
__constants__ = ['dim', 'eps']
def __init__(self, dim=1, eps=1e-8):
super(CosineSimilarity, self).__init__()
self.dim = dim
self.eps = eps
def forward(self, x1, x2):
return F.cosine_similarity(x1, x2, self.dim, self.eps)