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The paper describes a scheme for symbolic manipulation of index expressions which arise as a by-product of the symbolic manipulation of expressions in the matrix calculi described by the authors in a previous paper. This scheme attempts program optimization by transforming the original algorithm rather than the machine code. The goal is to automatically generate code for handling the tedious address calculations necessitated by complicated data structures. The paper is therefore preoccupied with "indexing by position." The relationship of "indexing by name" and "indexing by position" is discussed. [ABSTRACT FROM AUTHOR]

As part of an effort to design and implement a Fortran compiler on the ILLIAC IV, an extended Fortran, called IVTRAN, has been developed. This language provides a means of expressing data and control structures suitable for exploiting ILLIAC IV parallelism. This paper reviews the hardware characteristics of the nine and singles out unconventiona features which could be expected to influence langluage (and compiler) design. The implications of these features for data layout and algorithm structure are discussed, and the conclusion is drawn that data allocation rather than code structuring is the crucial ILLIAC optimization problem. A satisfactory method of data allocation is then presented. Language structures to utilize this storage method and express parallel algorithms are described. [ABSTRACT FROM AUTHOR]

A brief description is given of the implementation technique for the replacement rule of the AMBIT programming language. The algorithm for the "AMBIT scan" and an example of its application are given. The algorithm is applicable to other members of the family of string transformation languages of which AMBIT is a member, and it provides a rationale for the design of the AMBIT language. [ABSTRACT FROM AUTHOR]

Discusses the design of a novel tree search scheme based on a bit vector representation of data. Optimization problem in the design of the tree search model; Proof that the same algorithm can be used to design either an ideal search tree or a bit-vector tree; Use of a small formatted file to illustrate the search scheme.

Since the logical structure of a data base can be represented by a tree or graph, it is quite natural for us to view the process of designing a data base as that of constructing a tree or a graph. A general method for constructing such a tree or graph is provided. There are three important elements in this general construction method; namely, a set of binary relations, an algorithm for constructing subsets of a set, and an algorithm for selecting an element from the given set of objects. The use of different relations and algorithms results in different information structures, as list, tree, ring, etc. Thus the problem of information organization and storage is reduced to that of defining relations and formulating algorithms under a given set of constraints. The results presented may be valuable to designers as useful design concepts, and may serve as a basis for developing a formal theory on the subject. [ABSTRACT FROM AUTHOR]

Presents a notation for describing the semantics of data structures. Implementation facility which could be a part of a programming language; Expression of the semantics of an algorithm; Efficiency of the structures.

Some basic facts about certain data structures are reviewed and an efficient algorithm is presented for constructing storage mapping function for n structure from the structure's definition. [ABSTRACT FROM AUTHOR]