May 1963 - Vol. 6 No. 5
Features
Internal and tape sorting using the replacement-selection technique
A general technique for sequencing unsorted records is presented. The technique is shown to be applicable for the first stage of a generalized sort program (the formation…
With a limited number of tape drives available for sorting, the polyphase technique of merging provides faster sorting than the conventional balanced method of merging.…
Read-backward polyphase sorting
Read-backward Polyphase sorting provides more efficient use of the tapes available to a sort than most other sorting techniques. Backward Polyphase produces a continuous…
A comparison between the polyphase and oscillating sort techniques
Read-backward Polyphase sorting provides more efficient use of the tapes available to a sort than most other sorting techniques. Backward Polyphase produces a continuous…
Little effort has been directed toward the creation of efficient, easy-to-use file merging routines. This lack of effort undoubtedly stems from the feeling that a process…
A tape file merge pattern generator
A routine is presented which specifies the sequence of merge cycles to effect the merging of sorted tape files. The routine is designed to minimize elapsed computer time…
Sorting nonredundant files—techniques used in the FACT compiler
Some typical file structures, including some called “non-redundant,” are examined, and the methods used in FACT to sort such files are discussed.
Sorting with large volume, random access, drum storage
An approach to sorting records is described using random access drum memory. The Sort program described is designed to be a generalized, self-generating sort, applicable…
An approach to the organization and structure of data on Bryant Disc File Memory Systems for sorting and performing other data processing functions is presented. The…
Some characteristics of sorting computing systems using random access storage devices
The substantial differences in characteristics of random access storage and tape devices dictate that concepts and objectives of computer program design be considered…
The COBOL-61 specifications have recently been augmented with a number of extensions, one of which is a SORT verb. COBOL was designed initially for use in the processing…
A method of comparing the time requirements of sorting methods
Formulas have been developed for estimating the sorting time required by most of the known internal sorting methods in terms of parameters describing the file to be…
This paper describes the application of several new techniques for sorting fixed-length records to the problem of variable-length record sorting. The techniques have been…
Conversion, reconversion and comparison techniques in variable-length sorting
The logic is described for converting highly variable input records into a format that can be easily and efficiently processed by a sorting program.1 The internal record…
Use of tree structures for processing files
In data processing problems, files are frequently used which must both be searched and altered. Binary search techniques are efficient for searching large files, but the…