secondo/Algebras/Distributed4/DPartition.h

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//paragraph [10] title: [{\Large \bf] [}]
//characters [1] tt: [\texttt{] [}]
//[secondo] [{\sc Secondo}]

[10] Definition of Class DPartition

Distributed Partition

2017-11-13: Sebastian J. Bronner $<$sebastian@bronner.name$>$

\tableofcontents

1 About this Class

This class provides all the logic for the [secondo] type ~dpartition~. The
individual member functions, static member functions, and supporting functions
are documented with the implementation, in "DPartition.cpp"[1].

The type ~dpartition~ provides partitioning of values into slots of a ~darray~
or ~dfarray~. There are two cases that need to be kept apart here. If the
~d[f]array~ manages a distributed relation, partitioning is performed with
respect to a specific attribute of that relation. The attribute and its type
become part of the subtype of ~dpartition~ "(dpartition (Code int))"[1]. If the
~darray~ manages a collection of values (~vector~, ~set~, ~multiset~), just the
type of the values contained in the collection is part of the subtype of
~dpartition~ "(dpartition int)"[1].

*/
#ifndef ALGEBRAS_DISTRIBUTED4_DPARTITION_H
#define ALGEBRAS_DISTRIBUTED4_DPARTITION_H

#include "../Distributed2/DArray.h"

namespace distributed4 {
  class DPartition {
    protected:
/*
2 Member Variables

*/
      std::map<double,uint32_t> partitioning;
      //TODO: for multi-dimensional partitions, use either a vector of vectors
      //(of vectors) or a map<int,int> of maps<int,int> (of maps<int,int>).
      std::string darray_name;
      std::pair<double,uint32_t>
        bufpartition{std::numeric_limits<double>::quiet_NaN(), 0};
/*
  * "partitioning"[1] contains all necessary boundary information to correlate
    any value with a slot. Each entry maps a lower value boundary to a slot
    number.

  * "darray\_name"[1] is the name of the ~d[f]array~ managing the slots of the
    data being partitioned.

  * "bufpartition"[1] is used when the values belonging to a partition from
    "partitioning"[1] are present in two slots. This happens when using
    ~moveslot~ and similar operators. The special value NaN signifies that
    "bufpartition"[1] is not in use.

*/
    public:
      DPartition(const std::map<double,uint32_t>&, const std::string&, const
          std::pair<double,uint32_t>& = std::pair<double,uint32_t>{});
      DPartition(const NList&, const NList&);

      ListExpr listExpr() const;
      void print(std::ostream&) const;
      uint32_t slot(double) const;
      double partition(uint32_t) const;
      std::string darrayName() const;
      distributed2::DArrayBase* darray() const;
      void checkContiguous(double, double) const;

      uint32_t allocateSlot(uint32_t, distributed2::DArrayBase*);
      void resetPartition(double, uint32_t);
      void insertPartition(double, uint32_t);
      void removePartition(double);
      void setBufferPartition(double, uint32_t);
      void clearBufferPartition();

      static std::string BasicType();
      static ListExpr Out(ListExpr, Word);
      static Word In(ListExpr, ListExpr, int, ListExpr&, bool&);
      static bool checkType(const NList&);
      static bool checkType(ListExpr);  // for consistency with other types
      static bool checkType(ListExpr, ListExpr&);  // for "Functions"

      struct Info: ConstructorInfo { Info(); };
      struct Functions: ConstructorFunctions<DPartition> { Functions(); };

    protected:
      DPartition();

    friend Word ConstructorFunctions<DPartition>::Create(const ListExpr);
    friend void* ConstructorFunctions<DPartition>::Cast(void*);
  };

  std::ostream& operator<<(std::ostream&, const
      std::map<double,uint32_t>&);
  std::ostream& operator<<(std::ostream&, const DPartition&);
}

#endif