111 lines
3.8 KiB
C++
111 lines
3.8 KiB
C++
/*
|
|
----
|
|
This file is part of SECONDO.
|
|
|
|
Copyright (C) 2021, University in Hagen, Department of Computer Science,
|
|
Database Systems for New Applications.
|
|
|
|
SECONDO is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2 of the License, or
|
|
(at your option) any later version.
|
|
|
|
SECONDO 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with SECONDO; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
----
|
|
|
|
//paragraph [1] Title: [{\Large \bf \begin {center}] [\end {center}}]
|
|
|
|
[1] Association Analysis Algebra Implementation
|
|
|
|
January 2021 - April 2021, P. Fedorow for bachelor thesis.
|
|
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include "Algebras/Relation-C++/RelationAlgebra.h" // rel, trel, tuple
|
|
#include "NestedList.h"
|
|
#include "Operator.h"
|
|
|
|
#include <random>
|
|
#include <vector>
|
|
|
|
namespace AssociationAnalysis {
|
|
|
|
// Type mapping for the genTransactions operator.
|
|
ListExpr genTransactionsTM(ListExpr args);
|
|
|
|
class getTransactionsLI {
|
|
public:
|
|
// Prepares the set of potentially frequent itemsets and everything else that
|
|
// is needed for the generation of transactions.
|
|
getTransactionsLI(std::size_t numOfTransactions,
|
|
std::size_t transactionSizeMean,
|
|
std::size_t frequentItemsetSizeMean,
|
|
std::size_t numOfFrequentItemsets, std::size_t numOfItems);
|
|
|
|
~getTransactionsLI() { this->tupleType->DeleteIfAllowed(); }
|
|
|
|
// Returns the next generated transaction as a tuple.
|
|
Tuple *getNext();
|
|
|
|
private:
|
|
// The amount of transactions to be generated.
|
|
std::size_t numOfTransactions;
|
|
|
|
// The amount of transactions already generated.
|
|
std::size_t t;
|
|
|
|
// Random number distributions that are used to generate transactions.
|
|
std::mt19937 gen;
|
|
std::poisson_distribution<int> genTransactionSize;
|
|
std::discrete_distribution<int> genPotentialFrequentItemset;
|
|
|
|
// Potentially frequent itemsets that are used to fill a generated
|
|
// transaction.
|
|
std::vector<std::vector<int>> potentialFrequentItemsets;
|
|
|
|
// While a transaction is generated some items of a chosen potentially
|
|
// frequent itemset are left out and will not be part of the transaction. The
|
|
// amount of items to be left out is specified for each potentially frequent
|
|
// itemset in this vector.
|
|
std::vector<double> corruptionLevels;
|
|
|
|
// Oversized transactions (a transaction is oversized if it is larger
|
|
// than the size generated by the genTransactionSize random number
|
|
// distribution) are allowed in half the cases. This boolean is used to
|
|
// implement this behavior.
|
|
bool allowOversizedTransaction;
|
|
|
|
// Describes the resulting tuple type: tuple(Id: int, Itemset: intset).
|
|
TupleType *tupleType;
|
|
};
|
|
|
|
// Value mapping for the genTransactions operator.
|
|
int genTransactionsVM(Word *args, Word &result, int message, Word &local,
|
|
Supplier s);
|
|
|
|
// Operator info for the genTransactions operator.
|
|
struct genTransactionsInfo : OperatorInfo {
|
|
genTransactionsInfo() : OperatorInfo() {
|
|
this->name = "genTransactions";
|
|
this->signature =
|
|
"int int int int int -> stream(tuple([Id: int, Itemset: intset]))";
|
|
this->syntax = "genTransaction(_, _, _, _, _)";
|
|
this->meaning =
|
|
"Generates a stream of transactions. The expected arguments are: the "
|
|
"number of transactions, the mean of the transaction size, the mean of "
|
|
"the frequent itemset size, the number of frequent itemsets and the "
|
|
"number of items.";
|
|
this->usesArgsInTypeMapping = true;
|
|
}
|
|
};
|
|
} // namespace AssociationAnalysis
|