FixedTimeSteppingCodeSnippets.py

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# This file is part of the ExaHyPE2 project. For conditions of distribution and 
# use, please see the copyright notice at www.peano-framework.org
import exahype2.solvers.FixedTimeSteppingCodeSnippets
 
 
class FixedTimeSteppingCodeSnippets( exahype2.solvers.FixedTimeSteppingCodeSnippets ):
  """
  
  Code snippet generator for fixed time stepping in the Runge-Kutta schemes
  
  """
  def __init__(self, normalised_time_step_size, use_enclave_tasking):
    self._normalised_time_step_size = normalised_time_step_size
    self._use_enclave_tasking       = use_enclave_tasking
 
 
  def create_start_time_step_implementation(self):
    """
  
    The outcome is used before we actually roll over the accumulation variables
    and other stuff.
  
    """
    predicate = """
      tarch::mpi::Rank::getInstance().isGlobalMaster() 
      and
      _maxGridCellHThisTimeStep>0.0
      and
      isFirstGridSweepOfTimeStep()
    """
  
    if self._use_enclave_tasking:
      predicate += """and (_solverState == SolverState::Primary or _solverState == SolverState::PrimaryAfterGridInitialisation) """
      
    return """
  if (""" + predicate + """) {
    logInfo( "startTimeStep()", "Solver {{SOLVER_NAME}}:" );
    logInfo( "startTimeStep()", "t       = " << _minTimeStampThisTimeStep );
    logInfo( "startTimeStep()", "dt      = " << getTimeStepSize() );
    logInfo( "startTimeStep()", "h_{min} = " << _minGridCellHThisTimeStep << " (individual grid cell within a patch)");
    logInfo( "startTimeStep()", "h_{max} = " << _maxGridCellHThisTimeStep << " (individual grid cell within a patch)" );
  }
"""
 
 
  def create_finish_time_step_implementation(self):
    return """
  if ( isLastGridSweepOfTimeStep() ) {
    assertion( _minGridCellH >= 0.0 );
    assertion( MaxAdmissibleGridCellH > 0.0 );
    if (_minGridCellHThisTimeStep <= MaxAdmissibleGridCellH) {
      _timeStepSize  = """ + str(self._normalised_time_step_size) + """ * _minGridCellHThisTimeStep / MaxAdmissibleGridCellH / {{RK_ORDER}} / {{RK_ORDER}};
    }
    else {
      _timeStepSize = 0.0;
    }
  }
"""