Search
Join ACM

Computing Profession

Advertisement

Research and Advances

History and summary of FORTRAN standardization development for the ASA

The American Standards Association (ASA) Sectional Committee X3 for Computers and Information Processing was established in 1960 under the sponsorship of the Business Equipment Manufacturers Association. ASA X 3 in turn established an X3.4 Sectional Subcommittee to work in the area of common programming language standards. On May 17, 1962, X3.4 established by resolution a working group, X3.4.3-FORTRAN to develop American Standard FORTRAN proposals.
Research and Advances

Joint inventorship of computers

The term joint inventorship asks but does not necessarily answer the question, “Who is the true inventor of a computer?” I will try to show how “wrong” inventors are joined, how such improper joinder can be avoided, and its dangers. While the law permits the addition or subtraction of improperly joined inventors, it does not permit the substitution of one set of inventors for another set of inventors. Thus, despite corrective weapons, there are some pitfalls which must be avoided.
Research and Advances

Computer programs are patentable

It is not surprising that computer programs are not listed in the patent statutes as one of the categories of patentable invention. When these categories were defined many years ago, computers and computer programs were unknown. Therefore, if computer programs are to be patentable within the framework of existing patent law they must fall within one of the specifically defined categories of processes, machines, manufactures or compositions of matter.
Research and Advances

A note on the formation of free list

The concept of an available-space list was introduced by Newell and Shaw [1] in 1957, and has since been incorporated into a number of different systems [2-5]. The available-space list (or “free list”) is a list of all available memory locations. It should initially be as large as possible, and ideally it would contain every cell not used by the program. The subject of this note is the initial formation of a free list on the IBM 7090-7094, using the FORTRAN II monitor, version 2. The method presented originated while the authors were working on an implementation of the WISP [5] system for the 7090 in cooperation with Prof. M. V. Wilkes and his colleagues.
and
Research and Advances

Machine controls for analysis of variance

A major problem in using the analysis of variance, as the number of factors increases, is the exponential rise in the number of interactions. Even though the experimenter may not be interested in these interactions it is impossible to ignore them in most experimental designs because of the problem of getting error terms. It is natural therefore to look to the computer to handle the bulk of work involved in computing the interactions. A program device to get the computer to do this is described.
Research and Advances

Final examination scheduling

A method for scheduling final examinations to yield a minimal number of student conflicts is described. The “minimization” is achieved by repetitively evaluating a nonlinear set of equations. Imbedded in the process is a random or Monte Carlo selection of assignments. As in such heuristic techniques, the solution may not be optimum and many solutions may be found which yield locally minimal results. Computer programs are described and empirical results given.
Research and Advances

Formal parsing systems

Automatic syntactic analysis has recently become important for both natural language data processing and syntax-directed compilers. A formal parsing system G = (V, &mgr;, T, R) consists of two finite disjoint vocabularies, V and T, a many-many map, &mgr;, from V onto T, and a recursive set R of strings in T called syntactic sentence classes. Every program for automatic syntactic analysis determines a formal parsing system. A directed production analyzer (I, T, X, &rgr;) is a nondeterministic pushdown-store machine with internal vocabulary I, input vocabulary T, and all productions of &rgr; in the form: (Z, a) → aY1 ··· Ym, Z, Yi &egr; I, a &egr; T. Every context-free language can be analyzed by a directed production analyzer.
Research and Advances

A method of syntax-checking ALGOL 60

A syntax checker was designed based on the syntax of ALGOL as described in the ALGOL 60 Report [Communications of the ACM, May 1960]. Since the definition of the elements of the language is recursive it seemed most desirable to design the syntax checker as a set of mutually recursive processors tied together by subroutines which perform certain bookkeeping functions. Because of the recursive nature of the language and of the syntax checker the problem of recovery after an error required much attention. A method was devised which permits most programs to be checked completely despite errors.
Research and Advances

An alternate checksum method

To increase reliability of transmission between magnetic tape and core storage on an IBM 7090/7094, blocks or records of data are often assigned a word called a logical checksum. This is a number derived from the block by some simple algorithm and as unique to it as possible. The method most commonly used to form a checksum is to add together every datum in the block by the ACL (add and carry logical) instruction.
Research and Advances

A compiler-building system developed by Brooker and Morris: including a comprehensive discussion of the major features of the system

In a number of articles published during the past two years, R. A. Brooker and D. Morris (joined by J. S. Rohl in their most recent paper) have presented a very interesting programming system that they have developed for the Ferranti Atlas computer. The present paper describes some of the major features of their system. It expands on some points that the original authors cover briefly, and treats only very lightly some topics to which they devote considerable space. The purpose of this paper is purely expository. Except in some very small details, and in some comments, it does not intentionally depart from or add to the material published in the listed references. In the opinion of the writer, systems of this kind are well worth implementing and will provide useful research tools in the development of languages and techniques. This opinion is true even when such systems turn out to be of limited usefulness in producing “production” compilers, where compiling speed and object code optimization may be considered more important than language flexibility and elegance or generality of system organization.

Shape the Future of Computing

ACM encourages its members to take a direct hand in shaping the future of the association. There are more ways than ever to get involved.

Get Involved

Communications of the ACM (CACM) is now a fully Open Access publication.

By opening CACM to the world, we hope to increase engagement among the broader computer science community and encourage non-members to discover the rich resources ACM has to offer.

Learn More