Interface + base class for equation modulus

docs/source/_rst/_code.rst

@@ -195,13 +195,31 @@ Equations and Differential Operators
 .. toctree::
     :titlesonly:
 
-    EquationInterface <equation/equation_interface.rst>
+    Equation Interface <equation/equation_interface.rst>
+    Base Equation <equation/base_equation.rst>
     Equation <equation/equation.rst>
-    SystemEquation <equation/system_equation.rst>
-    Equation Factory <equation/equation_factory.rst>
+    System Equation <equation/system_equation.rst>
     Differential Operators <operator.rst>
 
 
+Equations Zoo
+---------------------------------------
+
+.. toctree::
+    :titlesonly:
+
+    Acoustic Wave Equation <equation/zoo/acoustic_wave_equation.rst>
+    Advection Equation <equation/zoo/advection_equation.rst>
+    Allen-Cahn Equation <equation/zoo/allen_cahn_equation.rst>
+    Diffusion-Reaction Equation <equation/zoo/diffusion_reaction_equation.rst>
+    Fixed Flux <equation/zoo/fixed_flux.rst>
+    Fixed Gradient <equation/zoo/fixed_gradient.rst>
+    Fixed Laplacian <equation/zoo/fixed_laplacian.rst>
+    Fixed Value <equation/zoo/fixed_value.rst>
+    Helmholtz Equation <equation/zoo/helmholtz_equation.rst>
+    Poisson Equation <equation/zoo/poisson_equation.rst>
+
+
 Problems
 --------------
 

docs/source/_rst/equation/base_equation.rst

@@ -0,0 +1,7 @@
+Base Equation
+====================
+
+.. currentmodule:: pina.equation.base_equation
+.. autoclass:: pina._src.equation.base_equation.BaseEquation
+   :members:
+   :show-inheritance:

docs/source/_rst/equation/zoo/acoustic_wave_equation.rst

@@ -0,0 +1,7 @@
+AcousticWaveEquation
+=====================
+.. currentmodule:: pina.equation.zoo.acoustic_wave_equation
+
+.. automodule:: pina._src.equation.zoo.acoustic_wave_equation
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/advection_equation.rst

@@ -0,0 +1,7 @@
+Advection Equation
+=====================
+.. currentmodule:: pina.equation.zoo.advection_equation
+
+.. automodule:: pina._src.equation.zoo.advection_equation
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/allen_cahn_equation.rst

@@ -0,0 +1,7 @@
+Allen Cahn Equation
+=====================
+.. currentmodule:: pina.equation.zoo.allen_cahn_equation
+
+.. automodule:: pina._src.equation.zoo.allen_cahn_equation
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/diffusion_reaction_equation.rst

@@ -0,0 +1,7 @@
+Diffusion Reaction Equation
+==============================
+.. currentmodule:: pina.equation.zoo.diffusion_reaction_equation
+
+.. automodule:: pina._src.equation.zoo.diffusion_reaction_equation
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/fixed_flux.rst

@@ -0,0 +1,7 @@
+Fixed Flux
+=====================
+.. currentmodule:: pina.equation.zoo.fixed_flux
+
+.. automodule:: pina._src.equation.zoo.fixed_flux
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/fixed_gradient.rst

@@ -0,0 +1,7 @@
+Fixed Gradient
+=====================
+.. currentmodule:: pina.equation.zoo.fixed_gradient
+
+.. automodule:: pina._src.equation.zoo.fixed_gradient
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/fixed_laplacian.rst

@@ -0,0 +1,7 @@
+Fixed Laplacian
+=====================
+.. currentmodule:: pina.equation.zoo.fixed_laplacian
+
+.. automodule:: pina._src.equation.zoo.fixed_laplacian
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/fixed_value.rst

@@ -0,0 +1,7 @@
+Fixed Value
+=====================
+.. currentmodule:: pina.equation.zoo.fixed_value
+
+.. automodule:: pina._src.equation.zoo.fixed_value
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/helmholtz_equation.rst

@@ -0,0 +1,9 @@
+Helmholtz Equation
+=====================
+.. currentmodule:: pina.equation.zoo.helmholtz_equation
+
+.. automodule:: pina._src.equation.zoo.helmholtz_equation
+
+.. autoclass:: pina._src.equation.zoo.helmholtz_equation.HelmholtzEquation
+    :members:
+    :show-inheritance:

docs/source/_rst/equation/zoo/poisson_equation.rst

@@ -0,0 +1,9 @@
+Poisson Equation
+=====================
+.. currentmodule:: pina.equation.zoo.poisson_equation
+
+.. automodule:: pina._src.equation.zoo.poisson_equation
+
+.. autoclass:: pina._src.equation.zoo.poisson_equation.PoissonEquation
+    :members:
+    :show-inheritance:

pina/_src/condition/data_manager.py

@@ -7,7 +7,7 @@
 from torch_geometric.data.batch import Batch
 from pina import LabelTensor
 from pina._src.core.graph import Graph, LabelBatch
-from ..equation.equation_interface import EquationInterface
+from pina._src.equation.base_equation import BaseEquation
 from .batch_manager import _BatchManager
 
 
@@ -39,7 +39,7 @@ def __new__(cls, **kwargs):
 
         # Does the data contain only tensors/LabelTensors/Equations?
         is_tensor_only = all(
-            isinstance(v, (torch.Tensor, LabelTensor, EquationInterface))
+            isinstance(v, (torch.Tensor, LabelTensor, BaseEquation))
             for v in kwargs.values()
         )
         # Choose the appropriate subclass, GraphDataManager or TensorDataManager

pina/_src/condition/domain_equation_condition.py

@@ -2,7 +2,7 @@
 
 from pina._src.condition.condition_base import ConditionBase
 from pina._src.domain.domain_interface import DomainInterface
-from pina._src.equation.equation_interface import EquationInterface
+from pina._src.equation.base_equation import BaseEquation
 
 
 class DomainEquationCondition(ConditionBase):
@@ -32,7 +32,7 @@ class DomainEquationCondition(ConditionBase):
     __fields__ = ["domain", "equation"]
 
     _avail_domain_cls = (DomainInterface, str)
-    _avail_equation_cls = EquationInterface
+    _avail_equation_cls = BaseEquation
 
     def __new__(cls, domain, equation):
         """
@@ -52,7 +52,7 @@ def __new__(cls, domain, equation):
 
         if not isinstance(equation, cls._avail_equation_cls):
             raise ValueError(
-                "The equation must be an instance of EquationInterface."
+                "The equation must be an instance of BaseEquation."
             )
 
         return super().__new__(cls)

pina/_src/condition/input_equation_condition.py

@@ -3,7 +3,7 @@
 from pina._src.condition.condition_base import ConditionBase
 from pina._src.core.label_tensor import LabelTensor
 from pina._src.core.graph import Graph
-from pina._src.equation.equation_interface import EquationInterface
+from pina._src.equation.base_equation import BaseEquation
 from pina._src.condition.data_manager import _DataManager
 
 
@@ -32,7 +32,7 @@ class InputEquationCondition(ConditionBase):
     # Available input data types
     __fields__ = ["input", "equation"]
     _avail_input_cls = (LabelTensor, Graph)
-    _avail_equation_cls = EquationInterface
+    _avail_equation_cls = BaseEquation
 
     def __new__(cls, input, equation):
         """
@@ -41,7 +41,7 @@ def __new__(cls, input, equation):
 
         :param input: The input data for the condition.
         :type input: LabelTensor | Graph |  list[Graph] | tuple[Graph]
-        :param EquationInterface equation: The equation to be satisfied over the
+        :param BaseEquation equation: The equation to be satisfied over the
             specified ``input`` data.
         :return: The subclass of InputEquationCondition.
         :rtype: pina.condition.input_equation_condition.
@@ -61,7 +61,7 @@ def __new__(cls, input, equation):
         # Check equation type
         if not isinstance(equation, cls._avail_equation_cls):
             raise ValueError(
-                "The equation must be an instance of EquationInterface."
+                "The equation must be an instance of BaseEquation."
             )
 
         return super().__new__(cls)
@@ -90,7 +90,7 @@ def equation(self):
         Return the equation associated with this condition.
 
         :return: Equation associated with this condition.
-        :rtype: EquationInterface
+        :rtype: BaseEquation
         """
         return self._equation
 
@@ -99,11 +99,9 @@ def equation(self, value):
         """
         Set the equation associated with this condition.
 
-        :param EquationInterface value: The equation to associate with this
+        :param BaseEquation value: The equation to associate with this
             condition
         """
-        if not isinstance(value, EquationInterface):
-            raise TypeError(
-                "The equation must be an instance of EquationInterface."
-            )
+        if not isinstance(value, BaseEquation):
+            raise TypeError("The equation must be an instance of BaseEquation.")
         self._equation = value

pina/_src/equation/base_equation.py

@@ -0,0 +1,67 @@
+"""Module for the Base Equation."""
+
+from abc import ABCMeta, abstractmethod
+import torch
+
+
+class BaseEquation(metaclass=ABCMeta):
+    """
+    Base class for all equations, implementing common functionality.
+
+    Equations are fundamental components in PINA, representing mathematical
+    constraints that must be satisfied by the model outputs. They can be passed
+    to :class:`~pina.condition.condition.Condition` objects to define the
+    conditions under which the model is trained.
+
+    All specific equation types should inherit from this class and implement its
+    abstract methods.
+
+    This class is not meant to be instantiated directly.
+    """
+
+    @abstractmethod
+    def residual(self, input_, output_, params_):
+        """
+        Evaluate the equation residual at the given inputs.
+
+        :param LabelTensor input_: The input points where the residual is
+            computed.
+        :param LabelTensor output_: The output tensor, potentially produced by a
+            :class:`torch.nn.Module` instance.
+        :param dict params_: An optional dictionary of unknown parameters, used
+            in :class:`~pina.problem.inverse_problem.InverseProblem` settings.
+            If the equation is not related to an inverse problem, this should be
+            set to ``None``. Default is ``None``.
+        :return: The residual values of the equation.
+        :rtype: LabelTensor
+        """
+
+    def to(self, device):
+        """
+        Move all tensor attributes to the specified device.
+
+        :param torch.device device: The target device to move the tensors to.
+        :return: The instance moved to the specified device.
+        :rtype: BaseEquation
+        """
+        # Iterate over all attributes of the Equation
+        for key, val in self.__dict__.items():
+
+            # Move tensors in dictionaries to the specified device
+            if isinstance(val, dict):
+                self.__dict__[key] = {
+                    k: v.to(device) if torch.is_tensor(v) else v
+                    for k, v in val.items()
+                }
+
+            # Move tensors in lists to the specified device
+            elif isinstance(val, list):
+                self.__dict__[key] = [
+                    v.to(device) if torch.is_tensor(v) else v for v in val
+                ]
+
+            # Move tensor attributes to the specified device
+            elif torch.is_tensor(val):
+                self.__dict__[key] = val.to(device)
+
+        return self