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Communications of the ACM

Table of Contents


A letter from the IEEE-CS president: the IEEE computer society and ACM


Representation of contours and regions for efficient computer search

A novel computer-searchable representation for the three basic pictorial features, contour maps, region coverage, and line structures, is described. The representation, which has practical storage requirements, provides a rapid …

The use of grammatical inference for designing programming languages

Both in designing a new programming language and in extending an existing language, the designer is faced with the problem of deriving a “natural” grammar for the language. We are proposing an interactive approach to the grammar …

A theory of discrete patterns and their implementation in SNOBOL4

The notion of a discrete pattern is formalized and certain properties deduced. A pattern is shown to be a generalization of a formal language. Algorithms for implementing the kinds of patterns in SNOBOL4 are given. The general …

Automatic errorbounds for simple zeros of analytic functions

The Cauchy-Ostrowski theorem on convergence of Newton iterates for an analytic function in one variable is extended to include computational errors using complex interval arithmetic. Several numerical examples are given for polynomials …

Reducing the retrieval time of scatter storage techniques

A new method for entering and retrieving information in a hash table is described. The method is intended to be efficient if most entries are looked up several times. The expected number of probes to look up an entry, predicted …

A software design and evaluation system

A critical failure of current software system design and implementation methodology is that the performance of a proposed design is not evaluated before it is actually implemented. In this paper the reasons for this failure are …

An overview of the ISPL computer systems design

This paper explores the advantages of the concurrent design of the language, operating system, and machine (via microcode) to create an interactive programming laboratory. It describes the synergistic effect that the freedom  …

Solution of the transcendental equation wew = x