C++ Array2D::isNoData方法代码示例

void Garbrecht_GradientTowardsLower(const Array2D<T> &elevations, const Array2D<d8_flowdir_t> &flowdirs, garbrecht_flat_type &flats, Array2D<int32_t> &inc1){
  int loops     = 0;
  int number_incremented = -1;
  std::cerr<<"Setting up the inc1 matrix..."<<std::endl;
  inc1.resize(elevations);
  inc1.setAll(0);

  while(number_incremented!=0){
    number_incremented=0;
    for(int i=0;i<(int)flats.size();i++){
      bool increment_elevation=true;
      int x=flats[i].x;
      int y=flats[i].y;
      for(int n=1;n<=8;n++){
        if( elevations(x+dx[n],y+dy[n])<elevations(x,y) &&
          flowdirs(x+dx[n],y+dy[n])!=NO_FLOW && !flowdirs.isNoData(x+dx[n],y+dy[n])
        ){
          increment_elevation=false;
          break;
        }
        else if(inc1(x+dx[n],y+dy[n])<loops &&
            elevations(x+dx[n],y+dy[n])==elevations(x,y)
        ){
          increment_elevation=false;
          break;
        }
      }
      if(increment_elevation){
        inc1(x,y)++;
        number_incremented++;
      }
    }
    loops++;
  }
}

void FindFlats(
  const Array2D<T>   &elevations,
  Array2D<int8_t>    &flats
){
  flats.resize(elevations);
  flats.setNoData(FLAT_NO_DATA);

  ProgressBar progress;

  progress.start( elevations.size() );

  #pragma omp parallel for
  for(int y=0;y<elevations.height();y++)
  for(int x=0;x<elevations.width();x++){
    if(elevations.isNoData(x,y)){
      flats(x,y) = FLAT_NO_DATA;
      continue;
    }

    if(elevations.isEdgeCell(x,y)){
      flats(x,y) = NOT_A_FLAT;
      continue;
    }

    //We'll now assume that the cell is a flat unless proven otherwise
    flats(x,y) = IS_A_FLAT;

    for(int n=1;n<=8;n++){
      const int nx = x+dx[n];
      const int ny = y+dy[n];
      if(elevations(nx,ny)<elevations(x,y) || elevations.isNoData(nx,ny)){
        flats(x,y) = NOT_A_FLAT;
        break;
      }
    }

    //We handled the base case just above the for loop
  }

  RDLOG_TIME_USE<<"Succeeded in = "<<progress.stop()<<" s";
}

static inline void TerrainProcessor(F func, const Array2D<T> &elevations, const float zscale, Array2D<float> &output){
  if(elevations.getCellLengthX()!=elevations.getCellLengthY())
    RDLOG_WARN<<"Cell X and Y dimensions are not equal!";

  output.resize(elevations);
  ProgressBar progress;

  progress.start(elevations.size());
  #pragma omp parallel for
  for(int y=0;y<elevations.height();y++){
    progress.update(y*elevations.width());
    for(int x=0;x<elevations.width();x++)
      if(elevations.isNoData(x,y))
        output(x,y) = output.noData();
      else
        output(x,y) = func(elevations,x,y,zscale);
  }
  RDLOG_TIME_USE<<"Wall-time = "<<progress.stop();
}

void dinf_upslope_area(
  const Array2D<T> &flowdirs,
  Array2D<U> &area
){
  Array2D<int8_t> dependency;
  std::queue<GridCell> sources;
  ProgressBar progress;

  std::cerr<<"\nA D-infinity Upslope Area"<<std::endl;
  std::cerr<<"C Tarboton, D.G. 1997. A new method for the determination of flow directions and upslope areas in grid digital elevation models. Water Resources Research. Vol. 33. pp 309-319."<<std::endl;

  std::cerr<<"p Setting up the dependency matrix..."<<std::endl;
  dependency.resize(flowdirs);
  dependency.setAll(0);

  std::cerr<<"p Setting up the area matrix..."<<std::endl;
  area.resize(flowdirs);
  area.setAll(0);
  area.setNoData(dinf_NO_DATA);

  bool has_cells_without_flow_directions=false;
  std::cerr<<"p Calculating dependency matrix & setting noData() cells..."<<std::endl;
  progress.start( flowdirs.size() );

  ///////////////////////
  //Calculate the number of "dependencies" each cell has. That is, count the
  //number of cells which flow into each cell.

  #pragma omp parallel for reduction(|:has_cells_without_flow_directions)
  for(int y=0;y<flowdirs.height();y++){
    progress.update( y*flowdirs.width() );
    for(int x=0;x<flowdirs.width();x++){
      //If the flow direction of the cell is NoData, mark its area as NoData
      if(flowdirs.isNoData(x,y)){
        area(x,y)       = area.noData();
        dependency(x,y) = 9;  //TODO: This is an unnecessary safety precaution. This prevents the cell from ever being enqueued (an unnecessary safe guard? TODO)
        continue;             //Only necessary if there are bugs below (TODO)
      }

      //If the cell has no flow direction, note that so we can warn the user
      if(flowdirs(x,y)==NO_FLOW){
        has_cells_without_flow_directions=true;
        continue;
      }

      //TODO: More explanation of what's going on here
      int n_high, n_low;
      int nhx,nhy,nlx,nly;
      where_do_i_flow(flowdirs(x,y),n_high,n_low);
      nhx=x+dinf_dx[n_high];
      nhy=y+dinf_dy[n_high];
      if(n_low!=-1){
        nlx = x+dinf_dx[n_low];
        nly = y+dinf_dy[n_low];
      }
      if( n_low!=-1 && flowdirs.inGrid(nlx,nly) && flowdirs(nlx,nly)!=flowdirs.noData() )
        dependency(nlx,nly)++;
      if( flowdirs.inGrid(nhx,nhy) && flowdirs(nhx,nhy)!=flowdirs.noData() )
        dependency(nhx,nhy)++;
    }
  }
  std::cerr<<"t Succeeded in = "<<progress.stop()<<" s"<<std::endl;

  if(has_cells_without_flow_directions)
    std::cerr<<"W \033[91mNot all cells had defined flow directions! This implies that there will be digital dams!\033[39m"<<std::endl;

  ///////////////////////
  //Find those cells which have no dependencies. These are the places to start
  //the flow accumulation calculation.

  std::cerr<<"p Locating source cells..."<<std::endl;
  progress.start( flowdirs.size() );
  for(int y=0;y<flowdirs.height();y++){
    progress.update( y*flowdirs.width() );
    for(int x=0;x<flowdirs.width();x++)
      if(flowdirs(x,y)==flowdirs.noData())
        continue;
      else if(flowdirs(x,y)==NO_FLOW)
        continue;
      else if(dependency(x,y)==0)
        sources.emplace(x,y);
  }
  std::cerr<<"t Source cells located in = "<<progress.stop()<<" s"<<std::endl;





  ///////////////////////
  //Calculate the flow accumulation by "pouring" a cell's flow accumulation
  //value into the cells below it, as indicated by the D-infinite flow routing
  //method.

  std::cerr<<"p Calculating up-slope areas..."<<std::endl;
  progress.start( flowdirs.numDataCells() );
  long int ccount=0;
  while(sources.size()>0){
    auto c = sources.front();
    sources.pop();

//.........这里部分代码省略.........

void FM_Freeman(
  const Array2D<E> &elevations,
  Array3D<float> &props,
  const double xparam
){
  RDLOG_ALG_NAME<<"Freeman (1991) Flow Accumulation (aka MFD, MD8)";
  RDLOG_CITATION<<"Freeman, T.G., 1991. Calculating catchment area with divergent flow based on a regular grid. Computers & Geosciences 17, 413–422.";
  RDLOG_CONFIG<<"p = "<<xparam;

  props.setAll(NO_FLOW_GEN);
  props.setNoData(NO_DATA_GEN);

  ProgressBar progress;
  progress.start(elevations.size());

  #pragma omp parallel for collapse(2)
  for(int y=0;y<elevations.height();y++)
  for(int x=0;x<elevations.width();x++){
    ++progress;

    if(elevations.isNoData(x,y)){
      props(x,y,0) = NO_DATA_GEN;
      continue;
    }

    if(elevations.isEdgeCell(x,y))
      continue;

    const E e    = elevations(x,y);

    double C = 0;
    for(int n=1;n<=8;n++){
      const int nx = x+dx[n];
      const int ny = y+dy[n];

      if(!elevations.inGrid(nx,ny))
        continue;
      if(elevations.isNoData(nx,ny)) //TODO: Don't I want water to drain this way?
        continue;

      const E ne = elevations(nx,ny);

      if(ne<e){
        const double rise = e-ne;
        const double run  = dr[n];
        const double grad = rise/run;
        const auto cval   = std::pow(grad,xparam);
        props(x,y,n)      = cval;
        C                += cval;
      }
    }

    if(C>0){
      props(x,y,0) = HAS_FLOW_GEN;

      C = 1/C; //TODO

      for(int n=1;n<=8;n++){
        auto &this_por = props(x,y,n);
        if(this_por>0)
          this_por *= C;
        else
          this_por = 0;
      }
    }
  }
  progress.stop();
}