template<class F>
class lf::mesh::utils::MeshFunctionGlobal< F >
MeshFunction wrapper for a simple function of physical coordinates.
- Template Parameters
-
| F | a functor type, offering an evaluation operator that acccepts a single coordinate vector. |
MeshFunctionGlobal essentially wraps a function object which represents a function defined on the mesh that depends only on the global coordinates. An example is e.g. the function \( \vec{x} \mapsto \norm{x}^2 \).
Requirements for F
F is a function object that should overload the call operator as follows:
std::vector< F_return_type > operator()(const mesh::Entity &e, const Eigen::MatrixXd &local) const
MeshFunction compliant evaluation operator.
which should return the value of the mesh function at the global coordinates x. The return type of the call operator can in principle be anything, but usually it is one of:
double for a scalar valued mesh functionstd::complex<double> for complex valued mesh functionEigen::Vector2d for a tensor valued mesh function.
For instance, a MeshFunctionGlobal object may be instantiated with a lambda function.
- Note
- For
DimGlobal==3, the call operator should of course accept a Eigen::Vector3d.
Use case
auto alpha = [](Eigen::Vector2d x) -> Eigen::Matrix<double, 2, 2> {
return (Eigen::Matrix<double, 2, 2>() << (3.0 + x[1]), x[0], x[0],
(2.0 + x[0]))
.finished();
};
const Eigen::Matrix<double, 0, 1> dummy;
const std::vector<Eigen::Matrix<double, 2, 2>> a{mf_alpha(*node, dummy)};
std::cout << a[0] << std::endl;
}
Definition at line 55 of file mesh_function_global.h.
