ExprUnitNode.h

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// # ExprUnitNode.h: Nodes representing unit handling in table select expression tree
// # Copyright (C) 2006
// # 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 TABLES_EXPRUNITNODE_H
#define TABLES_EXPRUNITNODE_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/tables/TaQL/ExprNodeRep.h>
#include <casacore/tables/TaQL/ExprNodeArray.h>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// <summary>
// Unit for scalar values in a table select expression tree
// </summary>
 
// <use visibility=local>
 
// <reviewed reviewer="UNKNOWN" date="before2004/08/25" tests="">
// </reviewed>
//
// <prerequisite>
// # Classes you should understand before using this one.
//   <li> TableExprNode
//   <li> Unit
// </prerequisite>
 
// <synopsis>
// This class represents a unit in a table select expression tree.
// It contains a unit conversion factor to convert the child to this unit.
// The factor is 1 if the child has no unit.
// </synopsis>
 
class TableExprNodeUnit : public TableExprNodeBinary {
 public:
  // Construct from the given child node and unit.
  TableExprNodeUnit(const TENShPtr& child, const Unit& unit);
 
  ~TableExprNodeUnit();
 
  // Calculate the conversion factor and return it.
  // It is static to be useful for TableExprNodeArrayFunc as well.
  static Double set(TableExprNodeRep& parent, const TENShPtr& child, const Unit& unit);
 
  // Create a new node if unit conversion is needed.
  // Otherwise return the current node.
  static TENShPtr useUnit(const TENShPtr& node, const Unit& unit);
 
  // Use <src>useUnit</src> to see if a conversion is needed.
  // If so, adapt the reference counts and replace the node.
  static void adaptUnit(TENShPtr& node, const Unit& unit);
 
  // Find the unit to be used and adapt the nodes to it.
  static Unit adaptUnits(TENShPtr& node1, TENShPtr& node2, TENShPtr& node3);
 
  // Get the unit factor.
  virtual Double getUnitFactor() const;
 
  virtual Double getDouble(const TableExprId& id);
  virtual DComplex getDComplex(const TableExprId& id);
 
 private:
  Double factor_p;
};
 
// <summary>
// Unit for array values in a table select expression tree
// </summary>
 
// <use visibility=local>
 
// <reviewed reviewer="UNKNOWN" date="before2004/08/25" tests="">
// </reviewed>
//
// <prerequisite>
// # Classes you should understand before using this one.
//   <li> TableExprNode
//   <li> Unit
// </prerequisite>
 
// <synopsis>
// This class represents a unit in a table select expression tree.
// It contains a unit conversion factor to convert the child to this unit.
// The factor is 1 if the child has no unit.
// </synopsis>
 
class TableExprNodeArrayUnit : public TableExprNodeArray {
 public:
  TableExprNodeArrayUnit(const TENShPtr& child, const Unit& unit);
  ~TableExprNodeArrayUnit();
  virtual Double getUnitFactor() const;
  virtual MArray<Double> getArrayDouble(const TableExprId& id);
  virtual MArray<DComplex> getArrayDComplex(const TableExprId& id);
 
 private:
  Double factor_p;
};
 
}  // namespace casacore
 
#endif