Files
PINA/pina/problem/zoo/inverse_poisson_2d_square.py
Filippo Olivo a0cbf1c44a Improve conditions and refactor dataset classes (#475)
* Reimplement conditions

* Refactor datasets and implement LabelBatch

---------

Co-authored-by: Dario Coscia <dariocos99@gmail.com>
2025-03-19 17:46:36 +01:00

57 lines
2.1 KiB
Python

"""Definition of the inverse Poisson problem on a square domain."""
import torch
from pina import Condition, LabelTensor
from pina.problem import SpatialProblem, InverseProblem
from pina.operator import laplacian
from pina.domain import CartesianDomain
from pina.equation.equation import Equation
from pina.equation.equation_factory import FixedValue
def laplace_equation(input_, output_, params_):
"""
Implementation of the laplace equation.
"""
force_term = torch.exp(
-2 * (input_.extract(["x"]) - params_["mu1"]) ** 2
- 2 * (input_.extract(["y"]) - params_["mu2"]) ** 2
)
delta_u = laplacian(output_, input_, components=["u"], d=["x", "y"])
return delta_u - force_term
class InversePoisson2DSquareProblem(SpatialProblem, InverseProblem):
"""
Implementation of the inverse 2-dimensional Poisson problem
on a square domain, with parameter domain [-1, 1] x [-1, 1].
"""
output_variables = ["u"]
x_min, x_max = -2, 2
y_min, y_max = -2, 2
data_input = LabelTensor(torch.rand(10, 2), ["x", "y"])
data_output = LabelTensor(torch.rand(10, 1), ["u"])
spatial_domain = CartesianDomain({"x": [x_min, x_max], "y": [y_min, y_max]})
unknown_parameter_domain = CartesianDomain({"mu1": [-1, 1], "mu2": [-1, 1]})
domains = {
"g1": CartesianDomain({"x": [x_min, x_max], "y": y_max}),
"g2": CartesianDomain({"x": [x_min, x_max], "y": y_min}),
"g3": CartesianDomain({"x": x_max, "y": [y_min, y_max]}),
"g4": CartesianDomain({"x": x_min, "y": [y_min, y_max]}),
"D": CartesianDomain({"x": [x_min, x_max], "y": [y_min, y_max]}),
}
conditions = {
"nil_g1": Condition(domain="g1", equation=FixedValue(0.0)),
"nil_g2": Condition(domain="g2", equation=FixedValue(0.0)),
"nil_g3": Condition(domain="g3", equation=FixedValue(0.0)),
"nil_g4": Condition(domain="g4", equation=FixedValue(0.0)),
"laplace_D": Condition(domain="D", equation=Equation(laplace_equation)),
"data": Condition(
input=data_input.extract(["x", "y"]),
target=data_output,
),
}