anchor.diff:      NewXR      = XR - DeltaX,                        % decrease XR to the left
       compute_fractal_data_file( DataFile, NewRowData,
                      NewXPix, NewXR, DeltaX, Width,
  -                   YPix, YI, DeltaY,Height,
  +                   YPix, YI, DeltaY, Height,
                      ConfigMap).
   
   %%%%%%%%%%%%%%%%%%%%%
  
positive.code:     % reset to begining of next row
      NewRowData = [],                                 % reset data for row to empty
      NewXPix    = Width,                              % reset to end of line
      NewXR      = maps:get(xRealRight,ConfigMap),     % reset to end of line
      NewYPix    = YPix - 1,                           % increment row
      NewYI      = YI - DeltaY,                          % increment row
      compute_fractal_data( NewRows, NewRowData,
                     NewXPix, NewXR, DeltaX, Width,
                     NewYPix, NewYI, DeltaY,Height,
                     ConfigMap);
  
  compute_fractal_data( Rows, RowData,       % row data computed so far
  
negative.code:     % reset to begining of next row
      NewRowData = [],                                 % reset data for row to empty
      NewXPix    = Width,                              % reset to end of line
      NewXR      = maps:get(xRealRight, ConfigMap),     % reset to end of line
      NewYPix    = YPix - 1,                           % increment row
      NewYI      = YI - DeltaY,                          % increment row
      compute_fractal_data_file( DataFile, NewRowData,
                     NewXPix, NewXR, DeltaX, Width,
                     NewYPix, NewYI, DeltaY, Height,
                     ConfigMap);
  
  compute_fractal_data_file( DataFile, RowData,       % row data computed so far
  