2021-05-07 15:19:22 +02:00

135 lines
4.8 KiB
Python

"""ProtoTorch components modules."""
import warnings
from typing import Tuple
import torch
from prototorch.components.initializers import (ComponentsInitializer,
EqualLabelInitializer,
ZeroReasoningsInitializer)
from prototorch.functions.initializers import get_initializer
from torch.nn.parameter import Parameter
class Components(torch.nn.Module):
"""Components is a set of learnable Tensors."""
def __init__(self,
number_of_components=None,
initializer=None,
*,
initialized_components=None,
dtype=torch.float32):
super().__init__()
# Ignore all initialization settings if initialized_components is given.
if initialized_components is not None:
self._components = Parameter(initialized_components)
if number_of_components is not None or initializer is not None:
wmsg = "Arguments ignored while initializing Components"
warnings.warn(wmsg)
else:
self._initialize_components(number_of_components, initializer)
def _initialize_components(self, number_of_components, initializer):
if not isinstance(initializer, ComponentsInitializer):
emsg = f"`initializer` has to be some subtype of " \
f"{ComponentsInitializer}. " \
f"You have provided: {initializer=} instead."
raise TypeError(emsg)
self._components = Parameter(
initializer.generate(number_of_components))
@property
def components(self):
"""Tensor containing the component tensors."""
return self._components.detach().cpu()
def forward(self):
return self._components
def extra_repr(self):
return f"components.shape: {tuple(self._components.shape)}"
class LabeledComponents(Components):
"""LabeledComponents generate a set of components and a set of labels.
Every Component has a label assigned.
"""
def __init__(self,
labels=None,
initializer=None,
*,
initialized_components=None):
if initialized_components is not None:
super().__init__(initialized_components=initialized_components[0])
self._labels = initialized_components[1]
else:
self._initialize_labels(labels)
super().__init__(number_of_components=len(self._labels),
initializer=initializer)
def _initialize_labels(self, labels):
if type(labels) == tuple:
num_classes, prototypes_per_class = labels
labels = EqualLabelInitializer(num_classes, prototypes_per_class)
self._labels = labels.generate()
@property
def component_labels(self):
"""Tensor containing the component tensors."""
return self._labels.detach().cpu()
def forward(self):
return super().forward(), self._labels
class ReasoningComponents(Components):
"""ReasoningComponents generate a set of components and a set of reasoning matrices.
Every Component has a reasoning matrix assigned.
A reasoning matrix is a Nx2 matrix, where N is the number of Classes. The
first element is called positive reasoning :math:`p`, the second negative
reasoning :math:`n`. A components can reason in favour (positive) of a
class, against (negative) a class or not at all (neutral).
It holds that :math:`0 \leq n \leq 1`, :math:`0 \leq p \leq 1` and :math:`0
\leq n+p \leq 1`. Therefore :math:`n` and :math:`p` are two elements of a
three element probability distribution.
"""
def __init__(self,
reasonings=None,
initializer=None,
*,
initialized_components=None):
if initialized_components is not None:
super().__init__(initialized_components=initialized_components[0])
self._reasonings = initialized_components[1]
else:
self._initialize_reasonings(reasonings)
super().__init__(number_of_components=len(self._reasonings),
initializer=initializer)
def _initialize_reasonings(self, reasonings):
if type(reasonings) == tuple:
num_classes, number_of_components = reasonings
reasonings = ZeroReasoningsInitializer(num_classes,
number_of_components)
self._reasonings = reasonings.generate()
@property
def reasonings(self):
"""Returns Reasoning Matrix.
Dimension NxCx2
"""
return self._reasonings.detach().cpu()
def forward(self):
return super().forward(), self._reasonings