Problem-oriented Language Research Articles

Process control software

This paper examines the nature of the software which is necessary so that a real-time computer may be used to control industrial processes. The general nature of a process control software system is discussed, and several methods for implementing such a system are examined. This paper is divided into several sections. First, the general structure of process control software systems is examined, and the programming problems associated with developing such a system are discussed. Then several tools for doing this programming are discussed, including problem-oriented languages, fill-in-the-blank programming systems, procedural programming languages, and the operating systems which are used to tie the different portions of a process control system together. This paper closes with a dicussion of future trends in process control software, and recent activities in developing software standards. It will be assumed that the reader is generally familiar with software with at least a passable knowledge of FORTRAN programming.

A computer system for transformational grammar

A comprehensive system for transformational grammar has been designed and implemented on the IBM 360/67 computer. The system deals with the transformational model of syntax, along the lines of Chomsky's Aspects of the Theory of Syntax . The major innovations include a full, formal description of the syntax of a transformational grammar, a directed random phrase structure generator, a lexical insertion algorithm, an extended definition of analysis, and a simple problem-oriented programming language in which the algorithm for application of transformations can be expressed. In this paper we present the system as a whole, first discussing the general attitudes underlying the development of the system, then outlining the system and discussing its more important special features. References are given to papers which consider some particular aspect of the system in detail.

A New Approach to Communication Software

The arguments for the necessity for the coexistence in the process control programming environment of both procedure-oriented languages like FORTRAN and problem-oriented languages like the Foxboro Company's LAM are presented. An example is given of how these different kinds of languages complement each other in use.

The expanding world of computers

The onward sweep of automatic processing of information is impeded by nine principal barriers: geography, cost, problem complexity, man-machine communication, inadequate sensors, lack of understanding, distance, time, and size. The main incentive for breaching these barriers is the universal need for processing information, ever more urgent as the greater part of human work activity changes from production to service. Computer developments in hardware, programming, time-sharing, education, data communication, and displays are judged by how effectively they remove these barriers, and their barrier-smashing potentialities indicate continued rapid expansion. Problem-oriented languages are particularly effective over the entire front. Online computers and time-sharing also rate high by this measure. Education and increased understanding are basic to all progress with the computer. This complex but powerful tool is the most important one available to governments and scientists to use in studying the problems being created by the population explosion, and in analyzing possible solutions.

R68-14 Microprogrammed Control in Problem-Oriented Languages

Hawryszkiewycz describes a dual-mode problem-oriented simulation language. He utilizes the microprogram capability of the CIRRUS computer to simulate the function of certain analog components in the solution of differential equations. These equations are presented to the analyst in block-diagram form.

Elektronisches rechnen in der analytischen chemie—IV : Algol-prozedur für ausgleichsfunktionen mit zwei konstanten

Optimal functions to interpret the relationship between different series of experimental data measured for similar objects or processes can be found by least squares adjustments of systematically varied functions. The mathematical structure of a universally applicable equation with two constants has been developed, and also two reduced equations with only one constant each. A calculation procedure, named AUSGL 2, is given for it in the problem-oriented language ALGOL for electronic computing. This procedure is a cybernetic “black box” and is used as a closed block within a simple frame programme for special problems. Its practical use presupposes only a little mathematical knowledge. By means of briefly outlined examples of the application of the function to bi-, ter- and multivalent adjustment of corresponding series of analytical results, a partially novel approach to a rational test and evaluation technique is shown. In a comprehensive example a functional analysis is made of two flame-photometric test series for Na and K in concentration ranges which result-through self-absorption and self-reversal-in non-linear calibration curves. By a simple frame programme a total of 8 (2 × 4) functions can be electronically evaluated in less than 17 min, whereas the time needed for conventional calculation is more than 170 times as long.

Interactive Graphics in Data Processing: A language for three-dimensional geometry

This paper argues that there is a need for a problem-oriented language to handle three-dimensional geometric information, and proposes a set of language facilities that illustrate how this need should be met. The emphasis is on the facilities needed for describing solid objects and their placement in space, and for defining and operating on configurations of Objects.

Microprogrammed Control in Problem-Oriented Languages

The application of microprogramming to problem-oriented languages is described in terms of a simulated analog system on a digital computer. Microprogramming facilitates the development of a problem-oriented machine code, which can be simply generated from the problem-oriented source language by simple translation. In the system described a problem defined by differential equations is drawn up in the form of an analog diagram. The diagram is coded into an analog-oriented source language which is converted by translation into the analog machine code. The system also allows the machine assembly code to be freely used with the analog input in coding the supervisory and interrupt facilities that are incorporated in the overall system design.

NAPSS—a numerical analysis problem-solving system

It has long been a recognized goal of computer programming technology to permit problems to be stated in languages appropriate to the fields in which the problems exist, and to provide for the solution of such problems as stated without requiring the services of specially trained programmers and analysts. Systems that provide these capabilities are “problem solving systems.” Their languages are problem-oriented languages. Systems of this type have been proposed and developed in a number of areas of engineering and design. Examples are the COGO system developed at MIT 1 and the DACS system developed by General Motors 2. At Purdue University during the past year we have been working on a design for a Numerical Analysis Problem Solving System (NAPSS). This paper discusses some of the features of the language and system design, and an approach through the development of so-called polyalgorithms to the design of the numerical analysis packages that are the essential elements of the problem solving system.

A table-making language

A problem-oriented language is discussed which is a useful tool for producing tabular reports. A program in the language is processed by the Tablemaker 2 system which is a compiler with compile-and-go options utilizing a top-down syntactic analyzer. The Tablemaker 2 language is concise and well-defined. One may describe data files with multiple-record structures, appropriately recode desired variables, control the production of sequences of files of n-dimensional arrays of weighted or unweighted counts, and perform arithmetic operations on each array and/or array sequence. Output processing to obtain printed results is specified in a particularly flexible and powerful manner within the Tablemaker 2 language. The user is allowed general data mapping within a defined overlay hierarchy to positions in variably formatted pages. Flexible format and label definition statements are provided, and external files including files of labels may be used. The use of the Tablemaker 2 language offers a simple and efficient approach to a type of problem normally handled by specialized time-consuming programming.

Information Handling

This paper explains how a small research effort in document retrieval led to the development of a generally useful package of information processing programs, first for a small (IBM 1401) computer and then for a large (IBM 7094) computer, to meet the growing demand, The approach is based ori standard programs for routine operations (editing, printing, searching) on information files, supplemented by a problem-oriented computer language for programming those tasks which the standard ‘ programs will not handle.The entire package has been carefully designed so that it can easily be taught to and used by people without previous computer experience, including clerical staff.

Random-Access Stored-Program Machines, an Approach to Programming Languages

A new class of machine models as a framework for the rational discussion of programming languages is introduced. In particular, a basis is provided for endowing programming languages with semantics. The notion of Random-Access Stored-Program Machine (RASP) is intended to capture some of the most salient features of the central processing unit of a modern digital computer. An instruction of such a machine is understood as a mapping from states (of the machine) into states. Some classification of instructions is introduced. It is pointed out in several theorems that programs of finitely determined instructions are properly more powerful if address modification is permitted than when it is forbidden, thereby shedding some light on the role of address modification in digital computers. The relation between problem-oriented languages (POL) and machine languages (ML) is briefly considered.

A Formal Definition of SOL

This paper gives a formal definition of SOL, a general-purpose algorithmic language useful for describing and simulating complex systems. SOL is described using meta-linguistic formulas as used in the definition of ALGOL 60. The principal differences between SOL and problem-oriented languages such as ALGOL or FORTRAN is that SOL includes capabilities for expressing parallel computation, convenient notations for embedding random quantities within arithmetic expressions and automatic means for gathering statistics about the elements involved. SOL differs from other simulation languages such as SIMSCRIPT primarily in simplicity of use and in readability since it is capable of describing models without including computer-oriented characteristics.

A Versatile Problem-Oriented Language for Engineers

The language of DAS (Digital Analog Simulation) simplifies communication between an engineer and a digital computer. Typical applications range from evaluating design formulas to simulating air defense systems. Training time is about two hours. To describe a problem in DAS language, the engineer first sketches a block diagram of the problem, using blocks describable by single words of the DAS vocabulary. These words include I (for integrator), S (for summer), TD (for time delay), and about twenty others. The output of one or more of the blocks in the basic diagram represents the solution to the problem. To provide for printing or plotting these outputs automatically, several kinds of read-out blocks are available. The DAS language description of the block diagram consists of a list of all the blocks used in the diagram and a related list showing which blocks provide inputs to those in the first list. This dual list is the DAS language description of the problem. A program for solving problems described in DAS language is available through SHARE. Engineers at Wright-Patterson Air Force Base use DAS language programs together with their own interpreter (called MIDAS) to aid in setting-up and checking-out large analog simulations. Both SHARE-DAS and MIDAS are designed for use with an IBM 7094 computer.

A parameterized compiler based on mechanical linguistics

A multiplicity of problem-oriented and machine-oriented languages for computer programming exists today. Many compilers have been constructed to translate between these languages. This report presents a technique for reducing the number of compilers necessary. A translation algorithm is presented, capable of being conveniently parameterized for various source language-target language pairs. Concepts are drawn from modern linguistic theory, and practical considerations in implementation and application are discussed.

Some remarks on the syntax of symbolic programming languages

This paper concerns some preliminary results of an investigation of certain syntactical features of symbolic programming languages (SPL), which is a part of a wider research in the field of problem-oriented languages for automatic processor construction [1]. Our main aim is to point out certain peculiar features of SPL's which yield a deeper insight into their linguistic nature from a formal point of view, in order to take further steps in the direction of finding a proper way to define them. The general approach suggested here might be of some interest in the broader field of general linguistics, since many languages, including natural languages, show similar properties.

Man-Machine Communications in Civil Engineering

The performance of engineering with the aid of a computer is basically a problem in man-machine communications. The conventional program approach to the use of a computer is incompatible with most engineering situations. The full potential usefulness of the computer is not realized, and the computer is sometimes misused. Hardware developments relate to efficient interaction between the man and the machine in an on-line mode. Software advances relate to problem-oriented programming languages for describing engineering situations to the computer. The combination of these developments represent a totally new level of man-machine communications ability which will materially change the role of the computer in engineering. Examples of the developments and their potential impact on engineering practice and engineering education are examined.

COMIT

The documentation of COMIT reflects the conviction that adequate user manuals are as much a part of a successful problem-oriented language system as is the compiler itself. Without adequate manuals, a language could not be easily learned or used, and much of the convenience that is implicit in the idea of a problem-oriented language would be lost. The COMIT manuals are thus as user-oriented as the language itself.

Syntactic analysis by digital computer

This paper provides an account of the Shadow language that is used to describe syntax and of a corresponding subroutine that enables a computer to perform syntactic analysis. The input to this subroutine consists of a string to be analyzed and a description of the syntax that is to be used. The syntax is expressed in the Shadow language. The output consists of a trace table that expresses the results of the syntactic analysis in a tabular form. Several versions of the subroutine and some associated programs have been in use now for over three years. The present account of the language and the subroutine contains a summary of material that has been described previously in unpublished reports and also some additional discussion of the work in relation to the more general questions of problem-oriented languages and string transformations.

Trajectory computation in a problem-oriented language

A new problem-oriented language, XYZ , is being used on an experimental basis for trajectory computation. In the experiment, XYZ is compared with FORTRAN to determine the relative advantages of the two systems for use in flight simulation work. The comparison is concerned with the steps of: problem definition, program design, coding, checkout, and production.