Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include "DataStructures/DataBox/DataBox.hpp"
       7             : #include "Time/AdaptiveSteppingDiagnostics.hpp"
       8             : #include "Time/Slab.hpp"
       9             : #include "Time/Tags/HistoryEvolvedVariables.hpp"
      10             : #include "Time/Time.hpp"
      11             : #include "Time/TimeStepId.hpp"
      12             : #include "Utilities/ErrorHandling/Assert.hpp"
      13             : #include "Utilities/Gsl.hpp"
      14             : #include "Utilities/TMPL.hpp"
      15             : 
      16             : /// \cond
      17             : namespace Tags {
      18             : struct AdaptiveSteppingDiagnostics;
      19             : template <typename Tag>
      20             : struct Next;
      21             : struct TimeStep;
      22             : struct TimeStepId;
      23             : template <typename StepperInterface>
      24             : struct TimeStepper;
      25             : }  // namespace Tags
      26             : class TimeStepper;
      27             : /// \endcond
      28             : 
      29             : /// \ingroup TimeGroup
      30             : /// Change the slab size, updating all quantities in the DataBox
      31             : /// depending on it.
      32             : ///
      33             : /// The end of the slab (in the appropriate direction for the
      34             : /// evolution's flow of time) will be set to \p new_slab_end.  The
      35             : /// time step is set to the same fraction of the new slab as it was of
      36             : /// the old.
      37             : template <typename DbTags>
      38           1 : void change_slab_size(const gsl::not_null<db::DataBox<DbTags>*> box,
      39             :                       const double new_slab_end) {
      40             :   const TimeStepId& old_time_step_id = db::get<Tags::TimeStepId>(*box);
      41             : 
      42             :   ASSERT(old_time_step_id.is_at_slab_boundary(),
      43             :          "Cannot change slab size in middle of slab: " << old_time_step_id);
      44             : 
      45             :   const Slab old_slab = old_time_step_id.step_time().slab();
      46             :   const double old_slab_end = old_time_step_id.time_runs_forward()
      47             :                                   ? old_slab.end().value()
      48             :                                   : old_slab.start().value();
      49             : 
      50             :   if (new_slab_end == old_slab_end) {
      51             :     return;
      52             :   }
      53             : 
      54             :   const TimeDelta& old_time_step = db::get<Tags::TimeStep>(*box);
      55             : 
      56             :   const Slab new_slab = old_time_step_id.time_runs_forward()
      57             :                             ? Slab(old_slab.start().value(), new_slab_end)
      58             :                             : Slab(new_slab_end, old_slab.end().value());
      59             :   // We are at a slab boundary, so the substep is 0.
      60             :   const TimeStepId new_time_step_id(
      61             :       old_time_step_id.time_runs_forward(), old_time_step_id.slab_number(),
      62             :       old_time_step_id.step_time().with_slab(new_slab));
      63             :   const auto new_time_step = old_time_step.with_slab(new_slab);
      64             : 
      65             :   const auto new_next_time_step_id =
      66             :       db::get<Tags::TimeStepper<TimeStepper>>(*box).next_time_id(
      67             :           new_time_step_id, new_time_step);
      68             : 
      69             :   db::mutate_apply<
      70             :       tmpl::push_front<Tags::get_all_history_tags<DbTags>,
      71             :                        ::Tags::Next<::Tags::TimeStepId>, ::Tags::TimeStep,
      72             :                        ::Tags::Next<::Tags::TimeStep>, ::Tags::TimeStepId,
      73             :                        ::Tags::AdaptiveSteppingDiagnostics>,
      74             :       tmpl::list<>>(
      75             :       [&new_next_time_step_id, &new_time_step, &new_time_step_id](
      76             :           const gsl::not_null<TimeStepId*> next_time_step_id,
      77             :           const gsl::not_null<TimeDelta*> time_step,
      78             :           const gsl::not_null<TimeDelta*> next_time_step,
      79             :           const gsl::not_null<TimeStepId*> local_time_step_id,
      80             :           const gsl::not_null<AdaptiveSteppingDiagnostics*> diags,
      81             :           const auto... histories) {
      82             :         const auto update_history = [&](const auto history) {
      83             :           if (not history->empty() and
      84             :               history->back().time_step_id == *local_time_step_id) {
      85             :             ASSERT(history->at_step_start(),
      86             :                    "Cannot change step size with substep data.");
      87             :             history->back().time_step_id = new_time_step_id;
      88             :           }
      89             :           return 0;
      90             :         };
      91             :         expand_pack(update_history(histories)...);
      92             : 
      93             :         *next_time_step_id = new_next_time_step_id;
      94             :         *time_step = new_time_step;
      95             :         *next_time_step = new_time_step;
      96             :         *local_time_step_id = new_time_step_id;
      97             :         ++diags->number_of_slab_size_changes;
      98             :       },
      99             :       box);
     100             : }