最上位桁優先式Radix-Sorting法の予備的研究

Abstract

Many kinds of sorting algorithms have been developed from the age of Punched Card System. Nowadays, any sorting algorithm can be called either (1) internal sorting methed or (2) external sorting method. Internal sorting method is used only when the number of records to be sorted (N) is not so large for the internal memory of the computer system. Larger memory space has become available with the aid of semiconductor technology. Therefore, it might be desired to develop a new internal sorting methed which works efficiently for very large N on the computer with huge internal memory space. This study investigated the internal sorting algorithm which works well when N is very large. The sorting algorithm presented in this study is developed for designing and constructing a data base system, such as marketing-research data base. The algorithm could be called a kind of radix-sorting method which starts at the most significant digit (MSD). After presenting the algorithms and associated programs written in BASIC language, suggestions for improving these algorithms are made. It is concluded that MSD-first radix-sorting method could be one of the most powerfull and applicable sorting methods in the near future.