Files
PINA/pina/geometry/exclusion_domain.py
Kush 0ea17d8ff4 Operation docs update (#154)
* Operation Interface Enhancement + Clarification
- added set notation to all the geometry operations
- added a warning to say sample_surface=True doesn't work

* minor fix docs

* fix operation_interface.py doc

---------

Co-authored-by: Dario Coscia <dariocoscia@Dario-Coscia.local>
Co-authored-by: Dario Coscia <93731561+dario-coscia@users.noreply.github.com>
2023-11-17 09:51:29 +01:00

111 lines
4.2 KiB
Python

"""Module for Location class."""
import torch
from .location import Location
from ..utils import check_consistency
from ..label_tensor import LabelTensor
import random
from .operation_interface import OperationInterface
class Exclusion(OperationInterface):
""" PINA implementation of Exclusion of Domains."""
def __init__(self, geometries):
"""
PINA implementation of Exclusion of Domains.
Given two sets :math:`A` and :math:`B` then the
domain difference is defined as:
..:math:
A \setminus B = \{x \mid x \in A \text{ and } x \in B\ \text{ and } x \not\in (A \text{ or } B)},
with :math:`x` a point in :math:`\mathbb{R}^N` and :math:`N`
the dimension of the geometry space.
:param list geometries: A list of geometries from 'pina.geometry'
such as 'EllipsoidDomain' or 'CartesianDomain'.
:Example:
# Create two ellipsoid domains
>>> ellipsoid1 = EllipsoidDomain({'x': [-1, 1], 'y': [-1, 1]})
>>> ellipsoid2 = EllipsoidDomain({'x': [0, 2], 'y': [0, 2]})
# Create a Exclusion of the ellipsoid domains
>>> exclusion = Exclusion([ellipsoid1, ellipsoid2])
"""
super().__init__(geometries)
def is_inside(self, point, check_border=False):
"""Check if a point is inside the Exclusion domain.
:param point: Point to be checked.
:type point: torch.Tensor
:param bool check_border: If True, the border is considered inside.
:return: True if the point is inside the Exclusion domain, False otherwise.
:rtype: bool
"""
flag = 0
for geometry in self.geometries:
if geometry.is_inside(point, check_border):
flag += 1
return flag == 1
def sample(self, n, mode='random', variables='all'):
"""Sample routine for exclusion domain.
:param n: Number of points to sample in the shape.
:type n: int
:param mode: Mode for sampling, defaults to 'random'.
Available modes include: random sampling, 'random'.
:type mode: str, optional
:param variables: pinn variable to be sampled, defaults to 'all'.
:type variables: str or list[str], optional
:Example:
# Create two Cartesian domains
>>> cartesian1 = CartesianDomain({'x': [0, 2], 'y': [0, 2]})
>>> cartesian2 = CartesianDomain({'x': [1, 3], 'y': [1, 3]})
# Create a Exclusion of the ellipsoid domains
>>> Exclusion = Exclusion([cartesian1, cartesian2])
>>> Exclusion.sample(n=5)
LabelTensor([[2.4187, 1.5792],
[2.7456, 2.3868],
[2.3830, 1.7037],
[0.8636, 1.8453],
[0.1978, 0.3526]])
>>> len(Exclusion.sample(n=5)
5
"""
if mode != 'random':
raise NotImplementedError(
f'{mode} is not a valid mode for sampling.')
sampled = []
# calculate the number of points to sample for each geometry and the remainder.
remainder = n % len(self.geometries)
num_points = n // len(self.geometries)
# sample the points
# NB. geometries as shuffled since if we sample
# multiple times just one point, we would end
# up sampling only from the first geometry.
iter_ = random.sample(self.geometries, len(self.geometries))
for i, geometry in enumerate(iter_):
sampled_points = []
# int(i < remainder) is one only if we have a remainder
# different than zero. Notice that len(geometries) is
# always smaller than remaider.
# makes sure point is uniquely inside 1 shape.
while len(sampled_points) < (num_points + int(i < remainder)):
sample = geometry.sample(1, mode, variables)
# if not self.is_inside(sample) --> will be the intersection
if self.is_inside(sample):
sampled_points.append(sample)
sampled += sampled_points
return LabelTensor(torch.cat(sampled), labels=self.variables)