FilterSequence.h

// This file is part of the Mamico project. For conditions of distribution
// and use, please see the copyright notice in Mamico's main folder, or at
// www5.in.tum.de/mamico
 
#pragma once
#include <functional>
#include <map>
#include <numeric>
#include <sys/time.h>
 
#include "coupling/filtering/interfaces/FilterInterface.h"
#include "coupling/indexing/CellIndex.h"
#include "tarch/configuration/ParseConfiguration.h"
 
// INCLUDE ALL FILTER HEADERS HERE
#include "coupling/filtering/filters/Constant.h"
#include "coupling/filtering/filters/Gauss.h"
#ifdef BUILD_WITH_EIGEN
#include "coupling/filtering/filters/POD.h"
#endif
#include "coupling/filtering/filters/ReadFromFile.h"
#include "coupling/filtering/filters/WriteToFile.h"
/*
#include "coupling/filtering/filters/Strouhal.h"
*/
#include "coupling/filtering/filters/Copy.h"
#include "coupling/filtering/filters/FilterFromFunction.h"
 
#if (COUPLING_MD_PARALLEL == COUPLING_MD_YES)
#include "coupling/filtering/SequentialFilter.h"
#endif
 
/*
 * Filter Sequences are used to group filters that will be applied in
 * chronological order. It is possible to customize
 *  - sequence input
 *  - filter parameters
 *  - modifiablitiy of filter list
 * per Filter Sequence.
 *
 * A generalized version of this concept is FilterJunction.
 * @author Felix Maurer
 */
 
namespace coupling {
namespace filtering {
template <unsigned int dim> class FilterSequence;
}
} // namespace coupling
 
template <unsigned int dim> class coupling::filtering::FilterSequence {
public:
  /*
   * Filter Sequences are constructed in
   * coupling::FilterPipeline::loadSequencesFromXML(...).
   */
  FilterSequence(const char* name, const std::vector<coupling::datastructures::CouplingCell<dim>*> inputCells,
#if (COUPLING_MD_PARALLEL == COUPLING_MD_YES)
                 MPI_Comm comm,
#endif
                 std::array<bool, 7> filteredValues = {true})
      : _name(name), _inputCellVector(inputCells),
#if (COUPLING_MD_PARALLEL == COUPLING_MD_YES)
        _comm(comm),
#endif
        _filteredValues(filteredValues), _isOutput(false), // potentially updated via loadSequencesFromXML
                                                           // calling setAsOutput()
        _isModifiable(true),                               // TODO: allow const sequences via XML attribute
        _timestepsElapsed(0) {
#ifdef DEBUG_FILTER_PIPELINE
    std::cout << PRINT_PREFIX() << "Now initializing." << std::endl;
#endif
 
    initCellVectors();
 
    bool filtersAnything = false;
    for (unsigned int i = 0; i < 7; i++)
      if (_filteredValues[i]) {
        filtersAnything = true;
        break;
      }
    if (!filtersAnything)
      std::cout << "Warning: Filter sequence " << _name
                << " does not filter any values. Add 'filtered-values' "
                   "attribute to XML element to change this."
                << std::endl;
#ifdef DEBUG_FILTER_PIPELINE
    std::cout << PRINT_PREFIX() << "Finished initialization." << std::endl;
#endif
  }
 
  virtual ~FilterSequence() {
    // Output average application times for all filters
#ifdef DEBUG_FILTER_PIPELINE
    if (IDXS.getRank() == 0) {
      std::cout << PRINT_PREFIX() << "Average application times for filters in this sequence in \u03BCs:" << std::endl;
      for (auto filter : _filters) {
        std::cout << "  " << filter->getType() << ": "
                  << (double)std::accumulate(_filterTimes[filter].begin(), _filterTimes[filter].end(), 0) / (double)_timestepsElapsed << std::endl;
      }
    }
#endif
 
    for (auto v1 : _cellVector1)
      delete v1;
    for (auto v2 : _cellVector2)
      delete v2;
    for (auto f : _filters)
      delete f;
#ifdef DEBUG_FILTER_PIPELINE
    std::cout << PRINT_PREFIX() << "Deconstructed." << std::endl;
#endif
  }
 
  /*
   * Each sequence operates on their own two copies of the md-to-macro domain.
   * Thus, before applying the sequence, we need to update these two copies.
   */
  void updateCellVectors() {
    for (unsigned int index = 0; index < _cellVector1.size(); index++) {
      *(_cellVector1[index]) = *(_inputCellVector[index]);
      *(_cellVector2[index]) = *(_inputCellVector[index]);
    }
  }
 
  /*
   * Applies all filters stored in _filters. Also measures performance times.
   */
  void operator()() {
    for (auto filter : _filters) {
      // measure time before application
      timeval before;
      gettimeofday(&before, NULL);
 
      // Apply the filter's operator()
      (*filter)();
 
      // measure time after application
      timeval after;
      gettimeofday(&after, NULL);
 
      // store time difference in usec in map
      _filterTimes[filter].push_back((after.tv_sec * 1000000 + after.tv_usec) - (before.tv_sec * 1000000 + before.tv_usec));
 
#ifdef DEBUG_FILTER_PIPELINE
      std::cout << PRINT_PREFIX() << "Applied filter " << filter->getType() << ". Application time: " << _filterTimes[filter].back() << "\u03BCs" << std::endl;
#endif
    }
    _timestepsElapsed++;
  }
 
  /*
   * Returns unique name identifier of this sequence.
   */
  const char* getName() { return _name; }
 
  bool isOutputToMacro() { return _isOutput; }
  void setAsOutputToMacro() {
#ifdef DEBUG_FILTER_PIPELINE
    std::cout << PRINT_PREFIX() << " Setting as pipeline to macro solver output." << std::endl;
#endif
    _isOutput = true;
  }
 
  /*
   * Modifiable sequences may have filters added dynamically via
   * FilterFromFunction.
   */
  bool isModifiable() { return _isModifiable; }
  void makeUnmodifiable() { _isModifiable = false; }
 
  std::vector<coupling::filtering::FilterInterface<dim>*> getFilters() { return _filters; }
 
  /*
   * All virtual functions below are redefined in case this sequence is actually
   * a FilterJunction. Read FilterJunction.h carefully.
   */
 
  /*
   * Interprets this sequence's filters' parameters (specified in
   * filter_pipeline.xml) and creates filter objects based on that. Since
   * different filters require vastly different parameters and thus different
   * means of instanciation, you need to add each new filter manually to this
   * method's "if/else-chain".
   *
   * Since after all filter objects are created it is possible to determine
   * whether _cellVector1 or _cellVector2 will be used as output, this is also
   * done in here.
   *
   * In addition to that, if this sequence is declared as unmodifibale, this
   * gets also detected in here.
   */
  virtual int loadFiltersFromXML(tinyxml2::XMLElement* sequenceNode);
 
  /*
   * This member function allows appendance and insertion of filters defined by
   * two processing functions to a modifiable sequence at runtime. Index -1
   * implies appending.
   */
  virtual void addFilter(
      const std::function<std::vector<double>(std::vector<double>, std::vector<std::array<unsigned int, dim>>)>* applyScalar,
      const std::function<std::vector<std::array<double, dim>>(std::vector<std::array<double, dim>>, std::vector<std::array<unsigned int, dim>>)>* applyVector,
      int filterIndex = -1);
 
  /*
   * Registers existence of a child sequence, i.e. a sequence using this
   * sequence's output as its input.
   */
  virtual void addChildSequence(coupling::filtering::FilterSequence<dim>* childSequence) { _childSequences.push_back(childSequence); }
 
  /*
   * Allows changing the input cells after init.
   */
  virtual void updateInputCellVector(const std::vector<coupling::datastructures::CouplingCell<dim>*> newInputCellVector) {
    _inputCellVector = newInputCellVector; // call copy constructor
 
    // cc this change to this sequence's first vector.
    if (!_filters.empty())
      _filters[0]->setInputCells(_inputCellVector);
  }
 
  /*
   * Which one of the two cell vectors are this sequence's output is solely
   * dependant on the number of filters the sequence contains, because each swap
   * (see loadFiltersFromXML) changes what is the sequence's final filter's
   * output.
   *
   * Some sequences have more than one output, thus the optional parameter. Has
   * no effect on a basic FilterSequence.
   */
  virtual const std::vector<coupling::datastructures::CouplingCell<dim>*>& getOutputCellVector(unsigned int outputIndex = 0) const {
    if (_filters.empty())
      return _inputCellVector;
 
    if (_filters.size() % 2 == 0)
      return _cellVector1;
 
    return _cellVector2;
  }
 
  virtual void printOutputCellVector() const {
    if (getOutputCellVector() == _inputCellVector)
      std::cout << "The sequence's input cell vector ";
    else if (getOutputCellVector() == _cellVector1)
      std::cout << "Cell vector 1 ";
    else if (getOutputCellVector() == _cellVector2)
      std::cout << "Cell vector 2 ";
    else { /*unreachable, see function definition above*/
    }
 
    std::cout << "will be used as output." << std::endl;
  }
 
  /*
   * This is trivial for the traditional sequence, i.e. non-Junction-case.
   */
  virtual unsigned int getNumInputs() { return 1; }
  virtual unsigned int getNumOutputs() { return 1; }
 
  /*
   * DUMMY HELPER FUNCTIONS
   */
 
  virtual void printFilters() {
    std::cout << "Filters in sequence " << _name << ": ";
    for (auto f : _filters)
      std::cout << f->getType() << " ";
    std::cout << std::endl;
  }
 
  virtual std::string PRINT_PREFIX() const { return std::string("   FS(").std::string::append(_name).std::string::append("): "); }
 
private:
  /*
   * Copies all input cells to _cellVector1 and _cellVector2.
   *
   * Used in consctructor.
   *
   * Not implemented by FilterJunction: Equivalent procedure can be found in
   * that class' constructor.
   */
  void initCellVectors();
 
protected:
  const char* _name;
 
  std::vector<coupling::datastructures::CouplingCell<dim>*> _inputCellVector; // points to (foreign) input vector
  std::vector<coupling::datastructures::CouplingCell<dim>*> _cellVector1;     // allocated for this sequence only
  std::vector<coupling::datastructures::CouplingCell<dim>*> _cellVector2;     // allocated for this sequence only
 
#if (COUPLING_MD_PARALLEL == COUPLING_MD_YES)
  MPI_Comm _comm;
#endif
 
  std::array<bool, 7> _filteredValues;
 
  bool _isOutput;     // true if this sequence's output vector (see above) is the
                      // Filter Pipeline's output
  bool _isModifiable; // true while filters can be added to sequence
 
  std::vector<coupling::filtering::FilterInterface<dim>*> _filters;
 
  // stores application times for all filters
  std::map<coupling::filtering::FilterInterface<dim>*, std::vector<unsigned int>> _filterTimes;
 
  // there must be some other place to get this from
  unsigned int _timestepsElapsed;
 
  // stores pointers to all sequences that use this sequence's output as their
  // input.
  std::vector<coupling::filtering::FilterSequence<dim>*> _childSequences;
};
 
// inlcude implementation
#include "coupling/filtering/sequencing/FilterSequence.cpph"