Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include <boost/math/special_functions/spherical_harmonic.hpp>
       7             : #include <cstddef>
       8             : #include <optional>
       9             : #include <vector>
      10             : 
      11             : #include "DataStructures/DataBox/Tag.hpp"
      12             : #include "DataStructures/DataVector.hpp"
      13             : #include "DataStructures/Tags/TempTensor.hpp"
      14             : #include "DataStructures/Tensor/EagerMath/DotProduct.hpp"
      15             : #include "DataStructures/Tensor/Slice.hpp"
      16             : #include "DataStructures/Variables.hpp"
      17             : #include "Domain/AreaElement.hpp"
      18             : #include "Domain/ExcisionSphere.hpp"
      19             : #include "Domain/Structure/Direction.hpp"
      20             : #include "Domain/Structure/IndexToSliceAt.hpp"
      21             : #include "Domain/Tags.hpp"
      22             : #include "Domain/TagsTimeDependent.hpp"
      23             : #include "Evolution/Systems/CurvedScalarWave/System.hpp"
      24             : #include "Evolution/Systems/CurvedScalarWave/Tags.hpp"
      25             : #include "Evolution/Systems/CurvedScalarWave/Worldtube/ElementActions/ReceiveWorldtubeData.hpp"
      26             : #include "Evolution/Systems/CurvedScalarWave/Worldtube/Inboxes.hpp"
      27             : #include "Evolution/Systems/CurvedScalarWave/Worldtube/SingletonChare.hpp"
      28             : #include "Evolution/Systems/CurvedScalarWave/Worldtube/Tags.hpp"
      29             : #include "NumericalAlgorithms/LinearOperators/DefiniteIntegral.hpp"
      30             : #include "NumericalAlgorithms/LinearOperators/PartialDerivatives.hpp"
      31             : #include "NumericalAlgorithms/SphericalHarmonics/RealSphericalHarmonics.hpp"
      32             : #include "Parallel/AlgorithmExecution.hpp"
      33             : #include "Parallel/GlobalCache.hpp"
      34             : #include "Parallel/Invoke.hpp"
      35             : #include "PointwiseFunctions/GeneralRelativity/Tags.hpp"
      36             : #include "Utilities/ErrorHandling/Assert.hpp"
      37             : #include "Utilities/Gsl.hpp"
      38             : #include "Utilities/TMPL.hpp"
      39             : 
      40             : /// \cond
      41             : namespace Tags {
      42             : struct TimeStepId;
      43             : }  // namespace Tags
      44             : /// \endcond
      45             : 
      46             : namespace CurvedScalarWave::Worldtube::Actions {
      47             : /*!
      48             :  * \brief Projects the regular field \f$\Psi^R\f$ and its time derivative
      49             :  * \f$\partial_t \Psi^R\f$ onto real spherical harmonics and sends the result to
      50             :  * the worldtube.
      51             :  *
      52             :  * \details The regular field is obtained by subtracting the singular/puncture
      53             :  * field from the numerical DG field.
      54             :  * All spherical harmonics are computed for \f$l <= n\f$, where \f$n\f$ is the
      55             :  * worldtube expansion order. The projection is done by integrating over the DG
      56             :  * grid of the element face using \ref definite_integral with the euclidean area
      57             :  * element. The worldtube adds up all integrals from the different elements to
      58             :  * obtain the integral over the entire sphere.
      59             :  *
      60             :  * DataBox:
      61             :  * - Uses:
      62             :  *    - `tags_to_slice_on_face`
      63             :  *    - `Worldtube::Tags::ExpansionOrder`
      64             :  *    - `Worldtube::Tags::FaceCoordinates<Dim, Frame::Inertial, true>`
      65             :  *    - `Worldtube::Tags::PunctureField`
      66             :  *    - `Worldtube::Tags::ExcisionSphere`
      67             :  *    - `Tags::TimeStepId`
      68             :  */
      69           1 : struct SendToWorldtube {
      70           0 :   static constexpr size_t Dim = 3;
      71           0 :   using tags_to_send = tmpl::list<CurvedScalarWave::Tags::Psi,
      72             :                                   ::Tags::dt<CurvedScalarWave::Tags::Psi>>;
      73           0 :   using tags_to_slice_to_face =
      74             :       tmpl::list<CurvedScalarWave::Tags::Psi, CurvedScalarWave::Tags::Pi,
      75             :                  CurvedScalarWave::Tags::Phi<Dim>,
      76             :                  gr::Tags::Shift<DataVector, Dim>, gr::Tags::Lapse<DataVector>,
      77             :                  domain::Tags::InverseJacobian<Dim, Frame::ElementLogical,
      78             :                                                Frame::Inertial>>;
      79             : 
      80             :   template <typename DbTagsList, typename... InboxTags, typename Metavariables,
      81             :             typename ArrayIndex, typename ActionList,
      82             :             typename ParallelComponent>
      83           0 :   static Parallel::iterable_action_return_t apply(
      84             :       db::DataBox<DbTagsList>& box,
      85             :       tuples::TaggedTuple<InboxTags...>& /*inboxes*/,
      86             :       Parallel::GlobalCache<Metavariables>& cache,
      87             :       const ArrayIndex& /*array_index*/, const ActionList /*meta*/,
      88             :       const ParallelComponent* const /*meta*/) {
      89             :     const auto& element_id = db::get<domain::Tags::Element<Dim>>(box).id();
      90             :     const auto& excision_sphere = db::get<Tags::ExcisionSphere<Dim>>(box);
      91             :     const auto direction = excision_sphere.abutting_direction(element_id);
      92             :     if (not direction.has_value()) {
      93             :       return {Parallel::AlgorithmExecution::Continue, std::nullopt};
      94             :     }
      95             :     const auto& mesh = db::get<domain::Tags::Mesh<Dim>>(box);
      96             :     const auto face_mesh = mesh.slice_away(direction->dimension());
      97             :     const size_t face_size = face_mesh.number_of_grid_points();
      98             : 
      99             :     Variables<tmpl::list<
     100             :         CurvedScalarWave::Tags::Psi, ::Tags::dt<CurvedScalarWave::Tags::Psi>,
     101             :         ::Tags::TempScalar<0>, ::Tags::TempScalar<1>, ::Tags::TempScalar<2>>>
     102             :         temporaries(face_size);
     103             :     auto& psi_regular_times_det =
     104             :         get(get<CurvedScalarWave::Tags::Psi>(temporaries));
     105             :     auto& dt_psi_regular_times_det =
     106             :         get(get<::Tags::dt<CurvedScalarWave::Tags::Psi>>(temporaries));
     107             :     auto& theta = get(get<::Tags::TempScalar<0>>(temporaries));
     108             :     auto& phi = get(get<::Tags::TempScalar<1>>(temporaries));
     109             :     auto& spherical_harmonic = get(get<::Tags::TempScalar<2>>(temporaries));
     110             :     const auto& face_quantities = db::get<Tags::FaceQuantities>(box).value();
     111             :     const auto& psi_numerical_face =
     112             :         get<CurvedScalarWave::Tags::Psi>(face_quantities);
     113             :     const auto& dt_psi_numerical_face =
     114             :         get<::Tags::dt<CurvedScalarWave::Tags::Psi>>(face_quantities);
     115             :     const auto& area_element =
     116             :         get<gr::surfaces::Tags::AreaElement<DataVector>>(face_quantities);
     117             :     const auto& puncture_field =
     118             :         db::get<Tags::CurrentIteration>(box) > 0
     119             :             ? db::get<Tags::IteratedPunctureField<Dim>>(box).value()
     120             :             : db::get<Tags::PunctureField<Dim>>(box).value();
     121             :     const auto& psi_puncture = get<CurvedScalarWave::Tags::Psi>(puncture_field);
     122             :     const auto& dt_psi_puncture =
     123             :         get<::Tags::dt<CurvedScalarWave::Tags::Psi>>(puncture_field);
     124             : 
     125             :     psi_regular_times_det =
     126             :         (get(psi_numerical_face) - get(psi_puncture)) * get(area_element);
     127             :     dt_psi_regular_times_det =
     128             :         (get(dt_psi_numerical_face) - get(dt_psi_puncture)) * get(area_element);
     129             :     const auto& centered_face_coords =
     130             :         db::get<Tags::FaceCoordinates<Dim, Frame::Inertial, true>>(box);
     131             :     ASSERT(centered_face_coords.has_value(),
     132             :            "Should be an abutting element here, but face coords are not "
     133             :            "calculated!");
     134             :     const auto& x = get<0>(centered_face_coords.value());
     135             :     const auto& y = get<1>(centered_face_coords.value());
     136             :     const auto& z = get<2>(centered_face_coords.value());
     137             : 
     138             :     const size_t order = db::get<Worldtube::Tags::ExpansionOrder>(box);
     139             :     const size_t num_modes = (order + 1) * (order + 1);
     140             :     Variables<tags_to_send> Ylm_coefs(num_modes);
     141             :     theta = atan2(hypot(x, y), z);
     142             :     phi = atan2(y, x);
     143             :     size_t index = 0;
     144             :     // project onto spherical harmonics
     145             :     for (size_t l = 0; l <= order; ++l) {
     146             :       // NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
     147             :       for (int m = -l; m <= static_cast<int>(l); ++m, ++index) {
     148             :         spherical_harmonic = ylm::real_spherical_harmonic(theta, phi, l, m);
     149             :         get(get<CurvedScalarWave::Tags::Psi>(Ylm_coefs)).at(index) =
     150             :             definite_integral(psi_regular_times_det * spherical_harmonic,
     151             :                               face_mesh);
     152             :         get(get<::Tags::dt<CurvedScalarWave::Tags::Psi>>(Ylm_coefs)).at(index) =
     153             :             definite_integral(dt_psi_regular_times_det * spherical_harmonic,
     154             :                               face_mesh);
     155             :       }
     156             :     }
     157             :     ASSERT(index == num_modes, "Internal indexing error. "
     158             :                                    << num_modes
     159             :                                    << " modes should have been calculated but "
     160             :                                    << index << " modes were computed.");
     161             : 
     162             :     auto& worldtube_component = Parallel::get_parallel_component<
     163             :         Worldtube::WorldtubeSingleton<Metavariables>>(cache);
     164             :     Parallel::receive_data<Worldtube::Tags::SphericalHarmonicsInbox<Dim>>(
     165             :         worldtube_component, db::get<::Tags::TimeStepId>(box),
     166             :         std::make_pair(element_id, std::move(Ylm_coefs)));
     167             :     if (db::get<Tags::CurrentIteration>(box) + 1 <
     168             :         db::get<Tags::MaxIterations>(box) ) {
     169             :       db::mutate<Tags::CurrentIteration>(
     170             :           [](const gsl::not_null<size_t*> current_iteration) {
     171             :             *current_iteration += 1;
     172             :           },
     173             :           make_not_null(&box));
     174             :       // still iterating, go to `IteratePunctureField`
     175             :       return {Parallel::AlgorithmExecution::Continue, std::nullopt};
     176             : 
     177             :     } else {
     178             :       db::mutate<Tags::CurrentIteration>(
     179             :           [](const gsl::not_null<size_t*> current_iteration) {
     180             :             *current_iteration = 0;
     181             :           },
     182             :           make_not_null(&box));
     183             :       // done iterating, get data for BCs
     184             :       return {Parallel::AlgorithmExecution::Continue,
     185             :               tmpl::index_of<ActionList, ReceiveWorldtubeData>::value};
     186             :     }
     187             :   }
     188             : };
     189             : }  // namespace CurvedScalarWave::Worldtube::Actions