LELAttribute.h

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// # LELAttribute.h: Ancillary information for the LEL letter classes
// # Copyright (C) 1997,1998,1999,2000,2001,2003
// # Associated Universities, Inc. Washington DC, USA.
// #
// # This library is free software; you can redistribute it and/or modify it
// # under the terms of the GNU Library General Public License as published by
// # the Free Software Foundation; either version 2 of the License, or (at your
// # option) any later version.
// #
// # This library is distributed in the hope that it will be useful, but WITHOUT
// # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
// # License for more details.
// #
// # You should have received a copy of the GNU Library General Public License
// # along with this library; if not, write to the Free Software Foundation,
// # Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
// #
// # Correspondence concerning AIPS++ should be addressed as follows:
// #        Internet email: casa-feedback@nrao.edu.
// #        Postal address: AIPS++ Project Office
// #                        National Radio Astronomy Observatory
// #                        520 Edgemont Road
// #                        Charlottesville, VA 22903-2475 USA
 
#ifndef LATTICES_LELATTRIBUTE_H
#define LATTICES_LELATTRIBUTE_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/casa/Arrays/IPosition.h>
#include <casacore/lattices/LEL/LELCoordinates.h>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// <summary>
// Ancillary information for the LEL letter classes.
// </summary>
//
// <use visibility=local>
//
// <reviewed reviewer="" date="yyyy/mm/dd" tests="" demos="">
// </reviewed>
//
// <prerequisite>
//   <li> <linkto class="Lattice"> Lattice</linkto>
//   <li> <linkto class="LatticeExpr"> LatticeExpr</linkto>
//   <li> <linkto class="LatticeExprNode"> LatticeExprNode</linkto>
//   <li> <linkto class="LELInterface"> LELInterface</linkto> and
//        derived classes
// </prerequisite>
//
// <etymology>
// Holds attribute information for the Lattice Expression
// Language letter classes.
// </etymology>
 
// <synopsis>
// The Lattice Expression Language letter classes provide
// expression objects. There is ancilliary information or
// attributes associated with these objects:
// <ul>
// <li> Scalar or lattice (i.e. array) or region.
// <li> In case of an array, is it a reduced array. I.e. is it an array
//      that has to be calculated beforehand (e.g. partialMax).
//      A scalar is always reduced.
// <li> Shape and tile shape of a lattice. This can be undefined.
// <li> Is the lattice masked?
// <li> Optionally coordinates of the lattice.
// </ul>
// Two attribute objects can be combined mirroring the combination of two
// expressions (like the addition of two lattices).
// Regions cannot be combined.
// </synopsis>
 
class LELAttribute {
 public:
  // Default constructor sets it as a scalar.
  LELAttribute();
 
  // Constructor sets it as lattice with given attributes.
  // An empty shape indicates that the shape is not known.
  LELAttribute(Bool isMasked, const IPosition& shape, const IPosition& tileShape,
               const LELCoordinates& coordinates, Bool isReduced = False);
 
  // Constructor sets it as a region with given attributes.
  explicit LELAttribute(uInt regionNdim);
 
  // Copy constructor (copy semantics)
  LELAttribute(const LELAttribute& attr);
 
  // Constructor that combines the two attributes given.
  // An array can be combined with a scalar.
  // If matchAxes is True and if two arrays are given, the shapes and
  // coordinates have to match exactly, otherwise one can be a subset of
  // the other (and LEL will auto-extend).
  LELAttribute(const LELAttribute& attrLeft, const LELAttribute& attrRight, Bool matchAxes = True);
 
  // Destructor
  ~LELAttribute();
 
  // Assignment (copy semantics)
  LELAttribute& operator=(const LELAttribute& other);
 
  // Is expression a scalar?
  Bool isScalar() const { return isScalar_p; }
 
  // Is expression a reduced array? A scalar is always reduced.
  Bool isReduced() const { return isReduced_p; }
 
  // Is expression a region?
  Bool isRegion() const { return isRegion_p; }
 
  // Is the expression result masked?
  Bool isMasked() const { return isMasked_p; }
 
  // What is the shape of the expression?
  const IPosition& shape() const { return shape_p; }
 
  // What is the tile shape of the expression?
  const IPosition& tileShape() const { return tileShape_p; }
 
  // What are the coordinates of the expression?
  const LELCoordinates& coordinates() const { return coords_p; }
 
  // Compare the coordinates and shapes to see if this is a subset of other.
  Int compareCoord(const LELAttribute& other) const;
 
 private:
  Bool isScalar_p;
  Bool isReduced_p;
  Bool isRegion_p;
  Bool isMasked_p;
  IPosition shape_p;
  IPosition tileShape_p;
  LELCoordinates coords_p;
};
 
}  // namespace casacore
 
#endif