Decomposition (computer Science)
Decomposition in computer science, also known as factoring, is breaking a complex problem or system into parts that are easier to conceive, understand, program, and maintain. Overview There are different types of decomposition defined in computer sciences: * In structured programming, ''algorithmic decomposition'' breaks a process down into well-defined steps. * Structured analysis breaks down a software system from the system context level to system functions and data entities as described by Tom DeMarco. * ''Object-oriented decomposition'', on the other hand, breaks a large system down into progressively smaller classes or objects that are responsible for some part of the problem domain. * According to Booch, algorithmic decomposition is a necessary part of object-oriented analysis and design, but object-oriented systems start with and emphasize decomposition into objects.Grady Booch (1994). ''Object-oriented Analysis and Design'' (2nd ed.). Redwood Cita, CA: Benjamin/Cummi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Computer Science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical disciplines (including the design and implementation of Computer architecture, hardware and Computer programming, software). Computer science is generally considered an area of research, academic research and distinct from computer programming. Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and for preventing Vulnerability (computing), security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Progr ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Model Of Computation
In computer science, and more specifically in computability theory and computational complexity theory, a model of computation is a model which describes how an output of a mathematical function is computed given an input. A model describes how units of computations, memories, and communications are organized. The computational complexity of an algorithm can be measured given a model of computation. Using a model allows studying the performance of algorithms independently of the variations that are specific to particular implementations and specific technology. Models Models of computation can be classified into three categories: sequential models, functional models, and concurrent models. Sequential models Sequential models include: * Finite state machines * Post machines (Post–Turing machines and tag machines). * Pushdown automata * Register machines ** Random-access machines * Turing machines * Decision tree model Functional models Functional models include: * Abstract re ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Subroutine
In computer programming, a function or subroutine is a sequence of program instructions that performs a specific task, packaged as a unit. This unit can then be used in programs wherever that particular task should be performed. Functions may be defined within programs, or separately in libraries that can be used by many programs. In different programming languages, a function may be called a routine, subprogram, subroutine, method, or procedure. Technically, these terms all have different definitions, and the nomenclature varies from language to language. The generic umbrella term ''callable unit'' is sometimes used. A function is often coded so that it can be started several times and from several places during one execution of the program, including from other functions, and then branch back (''return'') to the next instruction after the ''call'', once the function's task is done. The idea of a subroutine was initially conceived by John Mauchly during his work on ENIAC, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Readability
Readability is the ease with which a reader can understand a written text. In natural language, the readability of text depends on its content (the complexity of its vocabulary and syntax) and its presentation (such as typographic aspects that affect legibility, like font size, line height, character spacing, and line length). Researchers have used various factors to measure readability, such as: * Speed of perception * Perceptibility at a distance * Perceptibility in peripheral vision * Visibility * Reflex blink technique * Rate of work (reading speed) * Eye movements * Fatigue in reading * Cognitively-motivated features * Word difficulty * N-gram analysis * Semantic Richness Higher readability eases reading effort and speed for any reader, but it makes a larger difference for those who do not have high reading comprehension. Readability exists in both natural language and programming languages though in different forms. In programming, things such as programmer comments, c ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Personal Information Management
Personal information management (PIM) is the study of the activities people perform in order to acquire or create, store, organize, maintain, retrieve, and use information items such as documents (paper-based and digital), web pages, and email messages for everyday use to complete tasks (work-related or not) and fulfill a person's various roles (as parent, employee, friend, member of community, etc.). One ideal of PIM is that people should always have the right information in the right place, in the right form, and of sufficient completeness and quality to meet their current need. Technologies and tools can help so that people spend less time with time-consuming and error-prone clerical activities of PIM (such as looking for and organising information). But tools and technologies can also overwhelm people with too much information leading to information overload. A special focus of PIM concerns how people organize and maintain personal information collections, and methods that ca ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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How To Solve It
''How to Solve It'' (1945) is a small volume by mathematician George Pólya describing methods of problem solving. Four principles ''How to Solve It'' suggests the following steps when solving a mathematical problem: # First, you have to ''understand the problem''. # After understanding, ''make a plan''. pp. 8–12 # ''Carry out the plan''. # ''Look back'' on your work. How could it be better? If this technique fails, Pólya advises: "If you cannot solve the proposed problem, try to solve first some related problem. Could you imagine a more accessible related problem?" First principle: Understand the problem "Understand the problem" is often neglected as being obvious and is not even mentioned in many mathematics classes. Yet students are often stymied in their efforts to solve it, simply because they don't understand it fully, or even in part. In order to remedy this oversight, Pólya taught teachers how to prompt each student with appropriate questions, depending on the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Event Partitioning
Event partitioning is an easy-to-apply systems analysis technique that helps the analyst organize requirements for large systems into a collection of smaller, simpler, minimally-connected, easier-to-understand "mini systems" / use cases. Overview The event-partitioning approach is explained by Stephen M. McMenamin and John F. Palmer in '' Essential Systems Analysis''. A brief version of the approach is described in the article on Data Flow Diagrams (DFDs). A more complete discussion is in Edward Yourdon's ''Just Enough Structured Analysis''. The description focuses on using the technique to create data flow diagrams, but it can be used to identify use cases as well. The premise of event partitioning is that systems exist to respond to external events: identify what happens in the business environment that requires planned responses, then define and build systems to respond according to the rules of the business. In particular, a business system exists to service the requests ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Duplicate Code
In computer programming, duplicate code is a sequence of source code that occurs more than once, either within a program or across different programs owned or maintained by the same entity. Duplicate code is generally considered undesirable for a number of reasons. A minimum requirement is usually applied to the quantity of code that must appear in a sequence for it to be considered duplicate rather than coincidentally similar. Sequences of duplicate code are sometimes known as code clones or just clones, the automated process of finding duplications in source code is called clone detection. Two code sequences may be duplicates of each other without being character-for-character identical, for example by being character-for-character identical only when white space characters and comments are ignored, or by being token-for-token identical, or token-for-token identical with occasional variation. Even code sequences that are only functionally identical may be considered duplicate cod ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Dynamization
In computer science, dynamization is the process of transforming a static data structure into a dynamic one. Although static data structures may provide very good functionality and fast queries, their utility is limited because of their inability to grow/shrink quickly, thus making them inapplicable for the solution of dynamic problems, where the amount of the input data changes. Dynamization techniques provide uniform ways of creating dynamic data structures. Decomposable search problems We define problem P of searching for the predicate M match in the set S as P(M,S). Problem P is ''decomposable'' if the set S can be decomposed into subsets S_i and there exists an operation + of result unification such that P(M,S) = P(M,S_0) + P(M,S_1) + \dots + P(M,S_n). Decomposition Decomposition is a term used in computer science to break static data structures into smaller units of unequal size. The basic principle is the idea that any decimal number can be translated into a representation ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Component-based Software Engineering
Component-based software engineering (CBSE), also called component-based development (CBD), is a branch of software engineering that emphasizes the separation of concerns with respect to the wide-ranging functionality available throughout a given software system. It is a reuse-based approach to defining, implementing and composing loosely coupled independent components into systems. This practice aims to bring about an equally wide-ranging degree of benefits in both the short-term and the long-term for the software itself and for organizations that sponsor such software. Software engineering practitioners regard components as part of the starting platform for service-orientation. Components play this role, for example, in web services, and more recently, in service-oriented architectures (SOA), whereby a component is converted by the web service into a ''service'' and subsequently inherits further characteristics beyond that of an ordinary component. Components can produce or ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Code Refactoring
In computer programming and software design, code refactoring is the process of restructuring existing computer code—changing the '' factoring''—without changing its external behavior. Refactoring is intended to improve the design, structure, and/or implementation of the software (its '' non-functional'' attributes), while preserving its functionality. Potential advantages of refactoring may include improved code readability and reduced complexity; these can improve the source codes maintainability and create a simpler, cleaner, or more expressive internal architecture or object model to improve extensibility. Another potential goal for refactoring is improved performance; software engineers face an ongoing challenge to write programs that perform faster or use less memory. Typically, refactoring applies a series of standardized basic ''micro-refactorings'', each of which is (usually) a tiny change in a computer program's source code that either preserves the behavior of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |