Software Engineering and Programming Languages
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COBOL (COmmon Business Oriented Language) is an English Language programming system which is capable of being implemented on a wide variety of electronic digital computers for use in the solution of business data processing problems.
The idea was conceived in May, 1959 at a meeting called in the Pentagon by Mr. Charles Phillips of the Office of the Assistant Secretary of Defense, Comptroller. The purpose of this meeting was to consider the desirability and the feasibility of establishing a common language for the programming of electronic computers for data processing. Representatives from computer user installations, both government and industrial, computer manufacturers, universities, and others concerned with computers were present. There was almost unanimous agreement that the project was both desirable and feasible. The COnference on DAta SYstems Languages (CODASYL) was established, and three committees were defined and staffed. These committees were the Short Range Committee, the Intermediate Range Committee, and the Long Range Committee. Each committee had its own goal and its own time scale. The coordination of the work to be performed was to be accomplished by an Executive Committee.
The suggestions in this paper are part of the terminology used in work for the University of Pennsylvania's Office of Computer Research and Education. The work is jointly supported by the National Science Foundation* and the Air Force Office of Scientific Research.†
An algorithm for equivalence declarations
Many algebraic translators provide the programmer with a limited ability to allocate storage. Of course one of the most desirable features of these translators is the extent to which they remove the burden of storage allocation from the programmer. Nevertheless, there are situations in which one wishes to make certain vectors and arrays contiguous, coincident, or overlapping. This is made possible in FORTRAN by the use of COMMON and EQUIVALENCE statements, in MAD by the use of PROGRAM COMMON, ERASABLE, and EQUIVALENCE statements, etc.
Operational compatability of systems—conventions
This project is engaged in (a) a program of research into the application of the concepts and techniques of modern data processing to the design of mechanical parts, and (b) the further development of automatic programming systems for numerically controlled machine tools. The project is a cooperative venture between the Computer Applications Group of the Electronic Systems Laboratory and the Design and Graphics Division of the Mechanical Engineering Department, and is sponsored by the Manufacturing Methods Division of the USAF Air Material Command through Contract AF-33(600)-40604.
Logic tables are an excellent way of developing and expressing the logic required in procedures, operations, systems and circuits. A set of rules for writing and using logic tables is explained by means of some simple examples. Then the logic structure of a vending machine is given in which two logic tables are used. Logic tables are two-dimensional in nature, enabling us to fully express and consider both the sequential and parallel aspects of logic. They can be compiled directly into a computer program and so eliminate the need for flow charting and hand coding.
The ALGOL 60 Report,* when first encountered, seems to describe a very complex language which will be difficult to learn. The “metalinguistic formulae” admirably serve the purpose of precisely specifying a language, but they are certainly not very readable for a beginner. However, experience has shown that once the report is explained it is in fact easy to learn ALGOL and to write algorithms in it. The language is so general and powerful it can handle an enormous class of problems.
It is not hard to learn those parts of ALGOL present in other compiler languages: how to write assignment and go to and for statements, etc. Indeed, a lot of the unnecessary restrictions imposed by other compiling languages have finally been lifted. But ALGOL also allows many unobvious things to be written, as we will see later, and herein lies a problem: ALGOL seems to have become too general. So many restrictions have been lifted that a lot of technical details crop up which are hard to learn and to use correctly. In this paper some of the more obscure features of the language are considered and their usefulness is discussed. Remarks are based on the authors' interpretations of the ALGOL 60 Report.
Design of an improved transmission/data processing code
Historically there has been strong difference of opinion in the construction of 6-bit (64-character) data codes, based upon whether the code is to be used for communications or data processing. This paper reports on investigation of an improved code which meets transmission requirements and requires very little modification for varied data processing usage.
An indirect chaining method for addressing on secondary keys
Methods for entering random-access files on the basis of one key are briefly surveyed. The widely used chaining method, based on a pseudo-random key transformation, is reviewed in more detail. An efficient generalization of the chaining method which permits recovery on additional keys is then presented.
Comparison of iterative methods for the calculation of nth roots
Three iterative methods for calculation of nth roots (including one proposed by the author) are compared in two ways: (1) Theoretical convergence estimates are given. (2) A new macro-compiler which estimates machine running time is used to compare the running time of the three methods for a variety of input data.
Recent contributions on the subject of counting the ones or reversing the digits of a binary word have prompted some rather more general observations on bitwise operations which treat each binary digit in a computer word as a separate entity.
Two subroutines for symbol manipulation with an algebraic compiler
The current University of North Carolina version of the IT Compiler [1, 2], as well as the GAT Compiler of Arden and Graham of the University of Michigan [3], have special “alphabetic read” and “alphabetic type” statements. On the UNIVAC 1105 these features allow the direct input or output of six-symbol words, each symbol being either an alphanumeric or special character. Internally, each symbol is represented by a six-bit binary coded decimal code. On the IBM 650, five-symbol words are processed, with each symbol represented internally by a two-digit decimal code.
Comment on a paper on parallel processing
The article by Lynn Yarbrough on Parallel Processing in the October Communications is interesting since it attracts attention to a subject which needs to be given increased consideration. His indictment of manufacturers for failing to provide what he feels is minimal to realizing the advantages of multi-programming is not applicable to STRETCH, however. It may be recalled that his specific complaint concerns the lack of protection of any program or monitor from the unpredictable actions of any other program. On page 15 of the STRETCH Data Processing System Reference Manual, we read: Address monitoring facilities are provided … The upper and lower boundaries of the storage area to be defined are placed in two address boundary registers. An alarm will be given when an address falls either inside or outside the defined area, whichever is desired. Storing in protected areas is normally suppressed.
The BKS system for the Philco-2000
The BKS System is a program sequencing system designed for the Philco-2000 computer to meet operational requirements of the Bettis and Knolls Atomic Power Laboratories. The Philco-2000 on which this system is being used has a 32,768-word memory, 16 tape transports on-line, and an electric typewriter on-line. The card-to-tape, card-to-printer, tape-to-card, tape-to-printer, and routine tape-to-tape operations are performed with off-line equipment.
A card format for reference files in information processing
This paper proposes a card format suitable for a variety of reference files in information processing. An 80-column IBM card is divided into two fields—reference material field (columns 1-67) and identification field (columns 68-80). The format for the reference material is flexible, while the format for the identification is rigid. The reference material includes basically an index, title, source, class, summary and cross reference for each entry. The identification includes basically codes for a matrix of descriptors, an entry number, and the kind, major interest, and source of the reference. The identification also provides a choice to identify material for personal as well as general files. Since this card format is sufficient to identify the material normally associated with reference files for books, articles, programming terms, hardware terms, equipment, machine systems, abbreviations, etc., it is suitable as a standard for card reference files in information processing.
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