113 lines
3.8 KiB
Python
113 lines
3.8 KiB
Python
import torch
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import pytest
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from pina import Condition, LabelTensor, Trainer
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from pina.problem import SpatialProblem
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from pina.operators import laplacian
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from pina.geometry import CartesianDomain
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from pina.model import FeedForward
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from pina.solvers import PINNInterface
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from pina.equation.equation import Equation
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from pina.equation.equation_factory import FixedValue
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def laplace_equation(input_, output_):
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force_term = (torch.sin(input_.extract(['x']) * torch.pi) *
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torch.sin(input_.extract(['y']) * torch.pi))
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delta_u = laplacian(output_.extract(['u']), input_)
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return delta_u - force_term
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my_laplace = Equation(laplace_equation)
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in_ = LabelTensor(torch.tensor([[0., 1.]]), ['x', 'y'])
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out_ = LabelTensor(torch.tensor([[0.]]), ['u'])
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in2_ = LabelTensor(torch.rand(60, 2), ['x', 'y'])
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out2_ = LabelTensor(torch.rand(60, 1), ['u'])
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class Poisson(SpatialProblem):
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output_variables = ['u']
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spatial_domain = CartesianDomain({'x': [0, 1], 'y': [0, 1]})
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conditions = {
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'gamma1': Condition(
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location=CartesianDomain({'x': [0, 1], 'y': 1}),
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equation=FixedValue(0.0)),
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'gamma2': Condition(
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location=CartesianDomain({'x': [0, 1], 'y': 0}),
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equation=FixedValue(0.0)),
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'gamma3': Condition(
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location=CartesianDomain({'x': 1, 'y': [0, 1]}),
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equation=FixedValue(0.0)),
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'gamma4': Condition(
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location=CartesianDomain({'x': 0, 'y': [0, 1]}),
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equation=FixedValue(0.0)),
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'D': Condition(
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input_points=LabelTensor(torch.rand(size=(100, 2)), ['x', 'y']),
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equation=my_laplace),
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'data': Condition(
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input_points=in_,
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output_points=out_),
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'data2': Condition(
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input_points=in2_,
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output_points=out2_)
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}
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def poisson_sol(self, pts):
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return -(torch.sin(pts.extract(['x']) * torch.pi) *
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torch.sin(pts.extract(['y']) * torch.pi)) / (2 * torch.pi**2)
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truth_solution = poisson_sol
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class FOOPINN(PINNInterface):
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def __init__(self, model, problem):
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super().__init__(models=[model], problem=problem,
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optimizers=[torch.optim.Adam],
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optimizers_kwargs=[{'lr' : 0.001}],
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extra_features=None,
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loss=torch.nn.MSELoss())
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def forward(self, x):
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return self.models[0](x)
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def loss_phys(self, samples, equation):
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residual = self.compute_residual(samples=samples, equation=equation)
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loss_value = self.loss(
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torch.zeros_like(residual, requires_grad=True), residual
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)
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self.store_log(loss_value=float(loss_value))
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return loss_value
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def configure_optimizers(self):
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return self.optimizers, []
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# make the problem
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poisson_problem = Poisson()
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poisson_problem.discretise_domain(100)
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model = FeedForward(len(poisson_problem.input_variables),
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len(poisson_problem.output_variables))
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model_extra_feats = FeedForward(
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len(poisson_problem.input_variables) + 1,
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len(poisson_problem.output_variables))
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def test_constructor():
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with pytest.raises(TypeError):
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PINNInterface()
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# a simple pinn built with PINNInterface
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FOOPINN(model, poisson_problem)
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def test_train_step():
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solver = FOOPINN(model, poisson_problem)
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trainer = Trainer(solver, max_epochs=2, accelerator='cpu')
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trainer.train()
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def test_log():
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solver = FOOPINN(model, poisson_problem)
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trainer = Trainer(solver, max_epochs=2, accelerator='cpu')
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trainer.train()
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# assert the logged metrics are correct
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logged_metrics = sorted(list(trainer.logged_metrics.keys()))
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total_metrics = sorted(
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list([key + '_loss' for key in poisson_problem.conditions.keys()])
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+ ['mean_loss'])
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assert logged_metrics == total_metrics |