摘要:

AbstractA garbage collection algorithm that permits a reference count storage reclamation scheme to collect circularly linked inaccessible structures is presented. The algorithm requires no additional information beyond that required by a reference count scheme. In particular, it does not require the garbage collector to be able to find pointersoutsidethe heap. The algorithm is most useful for augmenting reference count storage reclamation systems and for implementing storage management systems on top of languages that do not provide their own. It is, however, considerably less efficient in space and time than conventional garbage collection systems.

ISSN:0038-0644    

DOI:10.1002/spe.4380140602

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractThe widely known Quicksort algorithm does not attempt to actively take advantage of partial order in sorting data. A simple change can be made to the Quicksort strategy to give a bestcase performance ofn, for ordered data, with a smooth transition toO(n log n)for random data. This algorithm (Transort) matches the performance of Sedgewick's claimed best implementation of Quicksort for random data.

ISSN:0038-0644    

DOI:10.1002/spe.4380140603

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractIn this paper a system for software development is described. This system consists of a general‐purpose macroprocessor and a set of service programs. The macroprocessor has been planned to work in a conversational environment and to this purpose a set of utilities has been inserted to aid the editing and the debugging of the macrodefinitions. Indeed the system allows the user to select, by means of commands, the flow of the operations to be executed and to choose when and how any program has to be expanded. The macroprocessor is easy to use and it is suitable to generate codes for both high‐level languages and assembler langua

ISSN:0038-0644    

DOI:10.1002/spe.4380140604

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractProductivity data are presented for a typical software development group working in small project teams. The wider aspects of productivity, including maintenance and release procedures, are considered. The group worked extensively with subcontractors, developing products by reusing software. The effect of this on the resulting products and the productivity is analysed: increased reliability was observed to be a consequence of software reuse, compared with first implementations.

ISSN:0038-0644    

DOI:10.1002/spe.4380140605

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractThe design and analysis of the structure of software systems has typically been based on purely qualitative grounds. In this paper we report on our positive experience with a set of quantitative measures of software structure. These metrics, based on the number of possible paths of information flow through a given component, were used to evaluate the design and implementation of a software system (the UNIX operating system kernel) which exhibits the interconnectivity of components typical of large‐scale software systems. Several examples are presented which show the power of this technique in locating a variety of both design and implementation defects. Suggested repairs, which agree with the commonly accepted principles of structured design and programming, are presented. The effect of these alterations on the structure of the system and the quantitative measurements of that structure lead to a convincing validation of the utility of information flow metric

ISSN:0038-0644    

DOI:10.1002/spe.4380140606

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractIn the UNIX environment, it is standard practice to use the make program to keep a system of interrelated modules up to date. When text files contain so‐called include statements referring to additional text files whose contents are to replace the statements, it soon becomes impractical, in a growing system, to manually maintain all make dependencies implied by these references. Therefore, the dependencies are often generated automatically from extracted include statements by various methods. However, the methods we have seen in use are too simplistic and either generate the wrong set of dependencies, or give only partial support. This paper describes an algorithm that can be used to generate make dependencies implied by include statements from a wide class of include mechanism

ISSN:0038-0644    

DOI:10.1002/spe.4380140607

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

摘要:

AbstractWe describe a computer graphics system for the display of meteorological fields (such as plots of temperature and pressure). Much of the design effort has gone into the command processor which uses the usual command format of VERB PARAMETER = VALUE … The parameter and values are defined in terms of a tree sructure and the program searches as much of the tree as is necessary to make an unambiguous indentification of a token (where such an identification is possible). Because of this, commands can generally be abbreviated to the format VERB VALUE. This shortened form is possible even when the value of the command parameter is numerical. This is achieved by always specifying the units of numerical values (such as 5 days, 24 hours, 1000 millibars, etc.). The command format allows the user to manipulate a number of fields to form derived fields such as the difference of two pressure forecasts. The use of defaults for all parameters (which change as the user requests plots), reduces the amount of typing required to a minimum. A ‘Help’ facility aids the user in his choice of com

ISSN:0038-0644    

DOI:10.1002/spe.4380140608

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380140610

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380140611

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380140612

出版商:John Wiley&Sons, Ltd.    

年代:1984

数据来源: WILEY