51 lines
1.7 KiB
Python
51 lines
1.7 KiB
Python
"""Module for the ParametricProblem class"""
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from abc import abstractmethod
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from .abstract_problem import AbstractProblem
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class ParametricProblem(AbstractProblem):
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"""
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The class for the definition of parametric problems, i.e., problems
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with parameters among the input variables.
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Here's an example of a spatial parametric ODE problem, i.e., a spatial
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ODE problem with an additional parameter `alpha` as coefficient of the
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derivative term.
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:Example:
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>>> from pina.problem import SpatialProblem, ParametricProblem
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>>> from pina.operators import grad
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>>> from pina import Condition, Span
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>>> import torch
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>>>
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>>> class ParametricODE(SpatialProblem, ParametricProblem):
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>>>
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>>> output_variables = ['u']
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>>> spatial_domain = Span({'x': [0, 1]})
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>>> parameter_domain = Span({'alpha': {1, 10}})
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>>>
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>>> def ode_equation(input_, output_):
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>>> u_x = grad(output_, input_, components=['u'], d=['x'])
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>>> u = output_.extract(['u'])
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>>> alpha = input_.extract(['alpha'])
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>>> return alpha * u_x - u
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>>>
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>>> def initial_condition(input_, output_):
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>>> value = 1.0
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>>> u = output_.extract(['u'])
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>>> return u - value
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>>>
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>>> conditions = {
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>>> 'x0': Condition(Span({'x': 0, 'alpha':[1, 10]}), initial_condition),
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>>> 'D': Condition(Span({'x': [0, 1], 'alpha':[1, 10]}), ode_equation)}
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"""
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@abstractmethod
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def parameter_domain(self):
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pass
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@property
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def parameters(self):
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return self.parameter_domain.variables
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