prototorch_models/prototorch/models/extras.py

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2021-06-04 20:20:32 +00:00
"""prototorch.models.extras
Modules not yet available in prototorch go here temporarily.
"""
import torch
from ..core.distances import euclidean_distance
from ..core.similarities import cosine_similarity
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def rescaled_cosine_similarity(x, y):
"""Cosine Similarity rescaled to [0, 1]."""
similarities = cosine_similarity(x, y)
return (similarities + 1.0) / 2.0
def shift_activation(x):
return (x + 1.0) / 2.0
def euclidean_similarity(x, y, variance=1.0):
d = euclidean_distance(x, y)
return torch.exp(-(d * d) / (2 * variance))
def gaussian(distances, variance):
return torch.exp(-(distances * distances) / (2 * variance))
def rank_scaled_gaussian(distances, lambd):
order = torch.argsort(distances, dim=1)
ranks = torch.argsort(order, dim=1)
return torch.exp(-torch.exp(-ranks / lambd) * distances)
class GaussianPrior(torch.nn.Module):
def __init__(self, variance):
super().__init__()
self.variance = variance
def forward(self, distances):
return gaussian(distances, self.variance)
class RankScaledGaussianPrior(torch.nn.Module):
def __init__(self, lambd):
super().__init__()
self.lambd = lambd
def forward(self, distances):
return rank_scaled_gaussian(distances, self.lambd)
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class ConnectionTopology(torch.nn.Module):
def __init__(self, agelimit, num_prototypes):
super().__init__()
self.agelimit = agelimit
self.num_prototypes = num_prototypes
self.cmat = torch.zeros((self.num_prototypes, self.num_prototypes))
self.age = torch.zeros_like(self.cmat)
def forward(self, d):
order = torch.argsort(d, dim=1)
for element in order:
i0, i1 = element[0], element[1]
self.cmat[i0][i1] = 1
self.cmat[i1][i0] = 1
self.age[i0][i1] = 0
self.age[i1][i0] = 0
self.age[i0][self.cmat[i0] == 1] += 1
self.age[i1][self.cmat[i1] == 1] += 1
self.cmat[i0][self.age[i0] > self.agelimit] = 0
self.cmat[i1][self.age[i1] > self.agelimit] = 0
def get_neighbors(self, position):
return torch.where(self.cmat[position])
def add_prototype(self):
new_cmat = torch.zeros([dim + 1 for dim in self.cmat.shape])
new_cmat[:-1, :-1] = self.cmat
self.cmat = new_cmat
new_age = torch.zeros([dim + 1 for dim in self.age.shape])
new_age[:-1, :-1] = self.age
self.age = new_age
def add_connection(self, a, b):
self.cmat[a][b] = 1
self.cmat[b][a] = 1
self.age[a][b] = 0
self.age[b][a] = 0
def remove_connection(self, a, b):
self.cmat[a][b] = 0
self.cmat[b][a] = 0
self.age[a][b] = 0
self.age[b][a] = 0
def extra_repr(self):
return f"(agelimit): ({self.agelimit})"
class CosineSimilarity(torch.nn.Module):
def __init__(self, activation=shift_activation):
super().__init__()
self.activation = activation
def forward(self, x, y):
epsilon = torch.finfo(x.dtype).eps
normed_x = (x / x.pow(2).sum(dim=tuple(range(
1, x.ndim)), keepdim=True).clamp(min=epsilon).sqrt()).flatten(
start_dim=1)
normed_y = (y / y.pow(2).sum(dim=tuple(range(
1, y.ndim)), keepdim=True).clamp(min=epsilon).sqrt()).flatten(
start_dim=1)
# normed_x = (x / torch.linalg.norm(x, dim=1))
diss = torch.inner(normed_x, normed_y)
return self.activation(diss)
class MarginLoss(torch.nn.modules.loss._Loss):
def __init__(self,
margin=0.3,
size_average=None,
reduce=None,
reduction="mean"):
super().__init__(size_average, reduce, reduction)
self.margin = margin
def forward(self, input_, target):
dp = torch.sum(target * input_, dim=-1)
dm = torch.max(input_ - target, dim=-1).values
return torch.nn.functional.relu(dm - dp + self.margin)
class ReasoningLayer(torch.nn.Module):
def __init__(self, num_components, num_classes, num_replicas=1):
super().__init__()
self.num_replicas = num_replicas
self.num_classes = num_classes
probabilities_init = torch.zeros(2, 1, num_components,
self.num_classes)
probabilities_init.uniform_(0.4, 0.6)
# TODO Use `self.register_parameter("param", Paramater(param))` instead
self.reasoning_probabilities = torch.nn.Parameter(probabilities_init)
@property
def reasonings(self):
pk = self.reasoning_probabilities[0]
nk = (1 - pk) * self.reasoning_probabilities[1]
ik = 1 - pk - nk
img = torch.cat([pk, nk, ik], dim=0).permute(1, 0, 2)
return img.unsqueeze(1)
def forward(self, detections):
pk = self.reasoning_probabilities[0].clamp(0, 1)
nk = (1 - pk) * self.reasoning_probabilities[1].clamp(0, 1)
numerator = (detections @ (pk - nk)) + nk.sum(1)
probs = numerator / (pk + nk).sum(1)
probs = probs.squeeze(0)
return probs