Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : #include <cstddef>
       6             : #include "DataStructures/DataBox/Prefixes.hpp"
       7             : #include "DataStructures/Variables.hpp"
       8             : #include "DataStructures/VariablesTag.hpp"
       9             : #include "Evolution/Systems/CurvedScalarWave/Worldtube/Tags.hpp"
      10             : #include "Time/Tags/HistoryEvolvedVariables.hpp"
      11             : #include "Time/TimeSteppers/TimeStepper.hpp"
      12             : #include "Utilities/Gsl.hpp"
      13             : /// \cond
      14             : namespace Tags {
      15             : template <typename StepperInterface>
      16             : struct TimeStepper;
      17             : }  // namespace Tags
      18             : /// \endcond
      19             : namespace CurvedScalarWave::Worldtube::Initialization {
      20             : /*!
      21             :  * \brief Initializes the time stepper and evolved variables used by the
      22             :  * worldtube system. Also sets `Tags::CurrentIteration` to 0.
      23             :  *
      24             :  * \details Sets the initial position and velocity of the particle to the values
      25             :  * specified in the input file. The time stepper history is set analogous to the
      26             :  * elements which use the same time stepper.
      27             :  */
      28           1 : struct InitializeEvolvedVariables {
      29           0 :   static constexpr size_t Dim = 3;
      30           0 :   using variables_tag = ::Tags::Variables<
      31             :       tmpl::list<Tags::EvolvedPosition<Dim>, Tags::EvolvedVelocity<Dim>>>;
      32           0 :   using dt_variables_tag = db::add_tag_prefix<::Tags::dt, variables_tag>;
      33             : 
      34           0 :   using simple_tags =
      35             :       tmpl::list<variables_tag, dt_variables_tag, Tags::CurrentIteration,
      36             :                  ::Tags::HistoryEvolvedVariables<variables_tag>>;
      37           0 :   using return_tags = simple_tags;
      38             : 
      39           0 :   using compute_tags = tmpl::list<>;
      40           0 :   using const_global_cache_tags = tmpl::list<>;
      41           0 :   using mutable_global_cache_tags = tmpl::list<>;
      42           0 :   using simple_tags_from_options = tmpl::list<Tags::InitialPositionAndVelocity>;
      43           0 :   using argument_tags = tmpl::list<::Tags::TimeStepper<TimeStepper>,
      44             :                                    Tags::InitialPositionAndVelocity>;
      45           0 :   static void apply(
      46             :       const gsl::not_null<Variables<
      47             :           tmpl::list<Tags::EvolvedPosition<Dim>, Tags::EvolvedVelocity<Dim>>>*>
      48             :           evolved_vars,
      49             :       const gsl::not_null<
      50             :           Variables<tmpl::list<::Tags::dt<Tags::EvolvedPosition<Dim>>,
      51             :                                ::Tags::dt<Tags::EvolvedVelocity<Dim>>>>*>
      52             :           dt_evolved_vars,
      53             :       const gsl::not_null<size_t*> current_iteration,
      54             :       const gsl::not_null<::Tags::HistoryEvolvedVariables<variables_tag>::type*>
      55             :           time_stepper_history,
      56             :       const TimeStepper& time_stepper,
      57             :       const std::array<tnsr::I<double, Dim>, 2>& initial_pos_and_vel) {
      58             :     *current_iteration = 0;
      59             :     const size_t starting_order =
      60             :         time_stepper.number_of_past_steps() == 0 ? time_stepper.order() : 1;
      61             :     *time_stepper_history =
      62             :         typename ::Tags::HistoryEvolvedVariables<variables_tag>::type{
      63             :             starting_order};
      64             :     evolved_vars->initialize(size_t(1), 0.);
      65             :     dt_evolved_vars->initialize(size_t(1), 0.);
      66             :     for (size_t i = 0; i < Dim; ++i) {
      67             :       get<Tags::EvolvedPosition<Dim>>(*evolved_vars).get(i)[0] =
      68             :           initial_pos_and_vel.at(0).get(i);
      69             :       get<Tags::EvolvedVelocity<Dim>>(*evolved_vars).get(i)[0] =
      70             :           initial_pos_and_vel.at(1).get(i);
      71             :     }
      72             :   }
      73             : };
      74             : }  // namespace CurvedScalarWave::Worldtube::Initialization