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