摘要
HA(hashing array),a new algorithm,for mining frequent itemsets of large database is proposed.It employs a structure hash array,ItemArray() to store the information of database and then uses it instead of database in later iteration.By this improvement,only twice scanning of the whole database is necessary,thereby the computational cost can be reduced significantly.To overcome the performance bottleneck of frequent 2-itemsets mining,a modified algorithm of HA,DHA(direct-addressing hashing and array) is proposed,which combines HA with direct-addressing hashing technique.The new hybrid algorithm,DHA,not only overcomes the performance bottleneck but also inherits the advantages of HA.Extensive simulations are conducted in this paper to evaluate the performance of the proposed new algorithm,and the results prove the new algorithm is more efficient and reasonable.
HA （hashing array）, a new algorithm, for mining frequent itemsets of large database is proposed. It employs a structure hash array, ltemArray （ ） to store the information of database and then uses it instead of database in later iteration. By this improvement, only twice scanning of the whole database is necessary, thereby the computational cost can be reduced significantly. To overcome the performance bottleneck of frequent 2-itemsets mining, a modified algorithm of HA, DHA （directaddressing hashing and array） is proposed, which combines HA with direct-addressing hashing technique. The new hybrid algorithm, DHA, not only overcomes the performance bottleneck but also inherits the advantages of HA. Extensive simulations are conducted in this paper to evaluate the performance of the proposed new algorithm, and the results prove the new algorithm is more efficient and reasonable.
