Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include "NumericalAlgorithms/TensorYlm/TensorYlm.hpp"
       7             : 
       8             : #include <array>
       9             : #include <complex>
      10             : #include <cstddef>
      11             : #include <cstdint>
      12             : 
      13             : #include "Utilities/Array.hpp"
      14             : 
      15           0 : namespace ylm::TensorYlm::helpers {
      16             : 
      17             : /// Defines the three Cartesian and three spherical basis vectors.
      18           0 : enum class BasisVector : uint8_t { x, y, z, l, m, mbar };
      19             : 
      20             : /// Returns a Cartesian BasisVector for every index.
      21             : template <size_t Rank>
      22           1 : std::array<BasisVector, Rank> to_cart_basis_vector(
      23             :     const cpp20::array<size_t, Rank>& indices);
      24             : 
      25             : /// Returns the m value associated with a Cartesian basis vector.
      26           1 : int bv_to_m(BasisVector basis_vector, int i);
      27             : 
      28             : /// Returns the prefactor k associated with a Cartesian basis vector.
      29           1 : std::complex<double> bv_to_k(BasisVector basis_vector, int i);
      30             : 
      31             : /// Returns a spherical BasisVector for every index.
      32             : template <size_t Rank>
      33           1 : std::array<BasisVector, Rank> to_sphere_basis_vector(
      34             :     const cpp20::array<size_t, Rank>& indices);
      35             : 
      36             : /// Returns minus the spinweight of a tetrad basis vector
      37           1 : int bv_to_s(BasisVector basis_vector);
      38             : 
      39             : /// Returns the spin weight of a tensor structure component in the spherical
      40             : /// basis.
      41             : template <typename TensorStructure>
      42           1 : int component_spin_weight(size_t component);
      43             : 
      44             : /// Computes the symmetry factor S that appears in various equations.
      45             : template <typename Symm>
      46           1 : double get_symm_factor(size_t src_multiplicity, size_t lbar);
      47             : 
      48             : /// Computes the (-1)^m factor that is used depending on whether the
      49             : /// coefficient normalization is Spherepack.
      50             : template <typename T>
      51           1 : constexpr T sign_m(const int m,
      52             :                    const CoefficientNormalization coefficient_normalization) {
      53             :   return coefficient_normalization == CoefficientNormalization::Spherepack and
      54             :                  m % 2 != 0
      55             :              ? static_cast<T>(-1)
      56             :              : static_cast<T>(1);
      57             : }
      58             : 
      59             : }  // namespace ylm::TensorYlm::helpers