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This paper modifies an earlier algorithm for converting decision tables into flowcharts which minimize subsequent execution time when compiled into a computer program. The algorithms considered in this paper perform limited search and, accordingly, do not necessarily result in globally optimal solutions. However, the greater search effort needed to obtain a globally optimal solution for complex decision tables is usually not justified by sufficient savings in execution time. There is an analogy between the problem of converting decision tables into efficient flowcharts and the well-understood problem in information theory of noiseless coding. The results of the noiseless coding literature are used to explore the limitations of algorithms used to solve the decision table problem. The analogy between the two problems is also used to develop improvements to the information algorithm in extending the depth of search under certain conditions and in proposing additional conditions to be added to the decision table. Finally, the information algorithm is compared with an algorithm proposed in a recent paper by Verhelst. [ABSTRACT FROM AUTHOR]

Using direct access computer files of bibliographic information, an attempt is made to overcome one of the problems often associated with information retrieval, namely, the maintenance and use of large dictionaries, the greater part of which is used only infrequently. A novel method is presented, which maps the hyperbolic frequency distribution of text characteristics onto a rectangular distribution. This is more suited to implementation on storage devices. This method treats text as a string of characters rather than words bounded by spaces, and chooses subsets of strings such that their frequencies of occurrence are more even than those of word types. The members of this subset are then used as index keys for retrieval. The rectangular distribution of key frequencies results in a much simplified file organization and promises considerable cost advantages. [ABSTRACT FROM AUTHOR]

Following the fixpoint theory of Scott, the semantics of computer programs are defined in terms of the least fixpoints of recursive programs. This allows not only the justification of all existing verification techniques, but also their extension to the handling, in a uniform manner of various properties of computer programs, including correctness, termination, and equivalence. [ABSTRACT FROM AUTHOR]

Pollack has proposed on algorithm for converting decision tables into flowcharts which minimize subsequent execution time when compiled into a computer program. Two modifications a this algorithm are proposed. The first relies on Shannon's noiseless coding theorem and the communications concept of entropy but does not completely test the ELSE Rule. The second modification completely tests the ELSE Rule but results in more executions than the first modification. Both modifications result in lower execution time than Pollack's algorithm. However, neither modification guarantees a globally optimal solution. [ABSTRACT FROM AUTHOR]

Focuses on proposed American Standard Code for Information Interchange that provides coded representations for a set of graphic and control characters having general utility in information interchange. Inclusion of several special characters intended to facilitate the representation of additional symbols or functions, a process known as code extension; Minimization of the risk of conflict between systems required to interoperate, and the possibility of including advance provision for code extension in the design of general purpose data handling systems; Establishment of a set of procedures for the representation of graphic symbols or control functions.

The article focuses on the possibility of programming a computer to compose music. The information encoded in a musical score relates to quantitative entities like pitch and time which makes it accessible to rational and mathematical analysis. A branch of applied mathematics known as information theory was taken up as a means of clarifying the aspect of musical communication. In theory, it is possible to construct tables of probabilities describing a musical style of an individual composer.

The article discusses an algorithm for Hu-Tucker minimum redundancy alphabetic coding method. This algorithm implements the Hu-Tucker method of variable length minimum redundancy alphabetic binary encoding. The symbols of the alphabet are considered to be an ordered forest of n terminal nodes. Two nodes in an ordered forest are said to be tentative-connecting if the sequence of nodes between the two given nodes is either empty or consists entirely of nonterminal nodes. An interval of nodes each pair of which is a tentative-connecting pair is called a tentative-connecting string. The original forest will, after a finite number of steps, be connected into a single tree. This tree will not, in general, satisfy the order-preserving requirement. However, it is shown the path lengths are feasible for the construction of a tree which does satisfy this requirement and is, moreover, minimal in cost. The present procedure finds a minimal cost tree whose longest path length and total path length are minimal.