A system for mechanically transforming formal program specifications into efficient implementations under interactive user control is described and illustrated through a detailed example. The potential benefits and pr...
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A system for mechanically transforming formal program specifications into efficient implementations under interactive user control is described and illustrated through a detailed example. The potential benefits and problems of this approach to software implementation are discussed.
It is known that the locality of reference of a program can be improved by restructuring it. One approach for program restructuring is to rearrange the order of relocatable program sectors and to repackage those secto...
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It is known that the locality of reference of a program can be improved by restructuring it. One approach for program restructuring is to rearrange the order of relocatable program sectors and to repackage those sectors of a program, that are needed within a relatively short time of one another, into the same virtual page. This approach needs no reprogramming of the source program. However, microscopic analysis of the internal structure of repackaged sectors often shows the existence of sectors only few portions of which are actually referenced while the sectors are in use.
An alerter is a program which monitors a database and reports to some user or program when a specified condition occurs. It may be that the condition is a complicated expression involving several entities in the datab...
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Structured programming has become one of the most widely discussed topics among DP professionals. Despite this, however, COBOL programmers, responsible for the majority of ‘bread and butter jobs’, have been left mos...
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Structured programming has become one of the most widely discussed topics among DP professionals. Despite this, however, COBOL programmers, responsible for the majority of ‘bread and butter jobs’, have been left mostly on their own. The article attempts to review the history of programming and list the areas essential for any future improvement and advancement of the programming profession, inclusive of systems analysis, education and training, and programming methodology. An alternative approach to structured programming in COBOL using decision tables is outlined and confronted with the concept of the so-called functional programming.
This paper investigates the performance of 35 dynamic memory allocation algorithms when used to service simulation programs as represented by 18 test cases. Algorithm performance was measured in terms of processing ti...
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This paper investigates the performance of 35 dynamic memory allocation algorithms when used to service simulation programs as represented by 18 test cases. Algorithm performance was measured in terms of processing time, memory usage, and external memory fragmentation. Algorithms maintaining separate free space lists for each size of memory block used tended to perform quite well compared with other algorithms. Simple algorithms operating on memory ordered lists (without any free list) performed surprisingly well. Algorithms employing power-of-two block sizes had favorable processing requirements hut generally unfavorable memory usage. Algorithms employing LIFO, FIFO, or memory ordered free lists generally performed poorly compared with others. [ABSTRACT FROM AUTHOR]
Three algorithms are presented as a set of Standard Fortran subroutines which compute the number of characters representable in a single storage unit, the number of bits representing a character, and the type of integ...
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