ExprDerNode.h

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// # ExprDerNode.h: Nodes representing scalars in table select expression tree
// # Copyright (C) 1994,1995,1996,1997,1999,2000,2001
// # 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_EXPRDERNODE_H
#define TABLES_EXPRDERNODE_H
 
// # Includes
#include <casacore/casa/aips.h>
#include <casacore/tables/TaQL/ExprNodeRep.h>
#include <casacore/tables/Tables/TableColumn.h>
#include <casacore/casa/Arrays/Vector.h>
#include <casacore/casa/BasicMath/Random.h>
 
namespace casacore {  // # NAMESPACE CASACORE - BEGIN
 
// # Forward Declarations
class TableColumn;
class Table;
 
// # This file defines classes derived from TableExprNode representing
// # the data type and operator in a table expression.
// #
// # Data types Bool, Int64, Double, DComplex and String are used.
// # Char, uChar, Short, uShort, Int, and uInt are converted to Int64,
// # Float to Double, and Complex to DComplex.
// # Binary operators +, -, *, /, ==, >=, >, <, <= and != are recognized.
// # Also &&, ||, parentheses and unary +, - and ! are recognized.
 
// <summary>
// Constant Bool in 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
// </prerequisite>
 
// <synopsis>
// This class represents a constant in a table select expression tree.
// This is also used to hold the value of a table keyword, which is
// constant over the entire table.
// </synopsis>
 
class TableExprNodeConstBool : public TableExprNodeBinary {
 public:
  TableExprNodeConstBool(const Bool& value);
  ~TableExprNodeConstBool() override = default;
  Bool getBool(const TableExprId& id) override;
 
 private:
  Bool value_p;
};
 
// <summary>
// Constant Int64 in 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
// </prerequisite>
 
// <synopsis>
// This class represents a constant in a table select expression tree.
// This is also used to hold the value of a table keyword, which is
// constant over the entire table.
// </synopsis>
 
class TableExprNodeConstInt : public TableExprNodeBinary {
 public:
  TableExprNodeConstInt(const Int64& value);
  ~TableExprNodeConstInt() override = default;
  Int64 getInt(const TableExprId& id) override;
  Double getDouble(const TableExprId& id) override;
  DComplex getDComplex(const TableExprId& id) override;
 
 private:
  Int64 value_p;
};
 
// <summary>
// Constant Double in 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
// </prerequisite>
 
// <synopsis>
// This class represents a constant in a table select expression tree.
// This is also used to hold the value of a table keyword, which is
// constant over the entire table.
// </synopsis>
 
class TableExprNodeConstDouble : public TableExprNodeBinary {
 public:
  TableExprNodeConstDouble(const Double& value);
  ~TableExprNodeConstDouble() override = default;
  Double getDouble(const TableExprId& id) override;
  DComplex getDComplex(const TableExprId& id) override;
 
 private:
  Double value_p;
};
 
// <summary>
// Constant DComplex in 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
// </prerequisite>
 
// <synopsis>
// This class represents a constant in a table select expression tree.
// This is also used to hold the value of a table keyword, which is
// constant over the entire table.
// </synopsis>
 
class TableExprNodeConstDComplex : public TableExprNodeBinary {
 public:
  TableExprNodeConstDComplex(const DComplex& value);
  ~TableExprNodeConstDComplex() override = default;
  DComplex getDComplex(const TableExprId& id) override;
 
 private:
  DComplex value_p;
};
 
// <summary>
// Constant String in 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
// </prerequisite>
 
// <synopsis>
// This class represents a constant in a table select expression tree.
// This is also used to hold the value of a table keyword, which is
// constant over the entire table.
// </synopsis>
 
class TableExprNodeConstString : public TableExprNodeBinary {
 public:
  TableExprNodeConstString(const String& value);
  ~TableExprNodeConstString() override = default;
  String getString(const TableExprId& id) override;
 
 private:
  String value_p;
};
 
// <summary>
// Constant Regex or StringDistance in 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
// </prerequisite>
 
// <synopsis>
// This class represents a constant in a table select expression tree.
// This is also used to hold the value of a table keyword, which is
// constant over the entire table.
// </synopsis>
 
class TableExprNodeConstRegex : public TableExprNodeBinary {
 public:
  TableExprNodeConstRegex(const TaqlRegex& value);
  ~TableExprNodeConstRegex() override = default;
  TaqlRegex getRegex(const TableExprId& id) override;
 
 private:
  TaqlRegex value_p;
  StringDistance dist_p;
};
 
// <summary>
// Constant Date in 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
// </prerequisite>
 
// <synopsis>
// This class represents a constant in a table select expression tree.
// This is also used to hold the value of a table keyword, which is
// constant over the entire table.
// </synopsis>
 
class TableExprNodeConstDate : public TableExprNodeBinary {
 public:
  TableExprNodeConstDate(const MVTime& value);
  ~TableExprNodeConstDate() override = default;
  Double getDouble(const TableExprId& id) override;
  MVTime getDate(const TableExprId& id) override;
 
 private:
  MVTime value_p;
};
 
// <summary>
// Scalar column in 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
// </prerequisite>
 
// <synopsis>
// This class represents a scalar column in a table select expression tree.
// When the select expression gets evaluated, the value of the
// given row in the column is used.
// </synopsis>
 
class TableExprNodeColumn : public TableExprNodeBinary {
 public:
  TableExprNodeColumn(const TableExprInfo&, const String& columnName);
  ~TableExprNodeColumn() override = default;
 
  // Get the table info for this column.
  TableExprInfo getTableInfo() const override;
 
  // Do not apply the selection.
  void disableApplySelection() override;
 
  // Re-create the column object for a selection of rows.
  void applySelection(const Vector<rownr_t>& rownrs) override;
 
  // Get the data type of this scalar column.
  Bool getColumnDataType(DataType&) const override;
 
  // Get the data for the given id.
  Bool getBool(const TableExprId& id) override;
  Int64 getInt(const TableExprId& id) override;
  Double getDouble(const TableExprId& id) override;
  DComplex getDComplex(const TableExprId& id) override;
  String getString(const TableExprId& id) override;
  const TableColumn& getColumn() const;
 
  // Get the data for the given rows.
  Array<Bool> getColumnBool(const Vector<rownr_t>& rownrs) override;
  Array<uChar> getColumnuChar(const Vector<rownr_t>& rownrs) override;
  Array<Short> getColumnShort(const Vector<rownr_t>& rownrs) override;
  Array<uShort> getColumnuShort(const Vector<rownr_t>& rownrs) override;
  Array<Int> getColumnInt(const Vector<rownr_t>& rownrs) override;
  Array<uInt> getColumnuInt(const Vector<rownr_t>& rownrs) override;
  Array<Int64> getColumnInt64(const Vector<rownr_t>& rownrs) override;
  Array<Float> getColumnFloat(const Vector<rownr_t>& rownrs) override;
  Array<Double> getColumnDouble(const Vector<rownr_t>& rownrs) override;
  Array<Complex> getColumnComplex(const Vector<rownr_t>& rownrs) override;
  Array<DComplex> getColumnDComplex(const Vector<rownr_t>& rownrs) override;
  Array<String> getColumnString(const Vector<rownr_t>& rownrs) override;
 
  // Get the column unit (can be empty).
  static Unit getColumnUnit(const TableColumn&);
 
 protected:
  TableExprInfo tableInfo_p;
  TableColumn tabCol_p;
  Bool applySelection_p;
};
 
// <summary>
// Rownumber in 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
// </prerequisite>
 
// <synopsis>
// This class represents the rownumber() function in a table
// select expression tree.
// The origin is stored to indicate whether the first rownumber
// should be zero (in C++)  or another value (1 in TaQL).
// </synopsis>
 
class TableExprNodeRownr : public TableExprNodeBinary {
 public:
  TableExprNodeRownr(const TableExprInfo&, uInt origin);
  ~TableExprNodeRownr() override = default;
  TableExprInfo getTableInfo() const override;
  Int64 getInt(const TableExprId& id) override;
 
 private:
  TableExprInfo tableInfo_p;
  uInt origin_p;
};
 
// <summary>
// Rowid in 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
// </prerequisite>
 
// <synopsis>
// This class represents the rowid() function in a table
// select expression tree.
// It is meant to get the original row number in a GIVING clause,
// but, of course, it can also be used in the SELECT clause.
// The row number returned is 0-based.
// </synopsis>
 
class TableExprNodeRowid : public TableExprNodeBinary {
 public:
  TableExprNodeRowid(const TableExprInfo&);
  ~TableExprNodeRowid() override = default;
  TableExprInfo getTableInfo() const override;
  void applySelection(const Vector<rownr_t>& rownrs) override;
  Int64 getInt(const TableExprId& id) override;
 
 private:
  TableExprInfo tableInfo_p;
  Vector<rownr_t> rownrs_p;
};
 
// <summary>
// Random number in 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
// </prerequisite>
 
// <synopsis>
// This class represents the rand() function in a table
// select expression tree.
// </synopsis>
 
class TableExprNodeRandom : public TableExprNodeBinary {
 public:
  TableExprNodeRandom(const TableExprInfo&);
  ~TableExprNodeRandom() override = default;
  TableExprInfo getTableInfo() const override;
  Double getDouble(const TableExprId& id) override;
 
 private:
  TableExprInfo tableInfo_p;
  MLCG generator_p;
  Uniform random_p;
};
 
}  // namespace casacore
 
#endif