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Type inference, sometimes calledtype reconstruction,[1]: 320refers to the automatic detection of thetypeof an expression in aformal language. These includeprogramming languagesand mathematicaltype systems, but alsonatural languagesin some branches ofcomputer scienceandlinguistics. In a typed language, a term's type de...
https://en.wikipedia.org/wiki/Type_inference
Incomputing,type introspectionis the ability of a program toexaminethetypeor properties of anobjectatruntime. Someprogramming languagespossess this capability. Introspection should not be confused withreflection, which goes a step further and is the ability for a program tomanipulatethe metadata, properties, and funct...
https://en.wikipedia.org/wiki/Type_introspection
typeof, alternately alsotypeOf, andTypeOf, is anoperatorprovided by severalprogramming languagesto determine thedata typeof avariable. This is useful when constructing programs that must accept multiple types of data without explicitly specifying the type. In languages that supportpolymorphismandtype casting, the type...
https://en.wikipedia.org/wiki/Typeof
Incomputer science,reflective programmingorreflectionis the ability of aprocessto examine,introspect, and modify its own structure and behavior.[1] The earliest computers were programmed in their nativeassembly languages, which were inherently reflective, as these original architectures could be programmed by defining...
https://en.wikipedia.org/wiki/Reflection_(computer_science)
Templatesare a feature of theC++programming language that allowsfunctionsandclassesto operate withgeneric types. This allows a function or classdeclarationto reference via a genericvariableanother different class (built-in or newly declareddata type) without creating full declaration for each of these different classes...
https://en.wikipedia.org/wiki/Template_(C%2B%2B)
Insystems engineering,information systemsandsoftware engineering, thesystems development life cycle(SDLC), also referred to as theapplication development life cycle, is a process for planning, creating, testing, and deploying aninformation system.[1]The SDLC concept applies to a range of hardware and software configura...
https://en.wikipedia.org/wiki/Systems_development_life_cycle
Computer-aided software engineering(CASE) is a domain of software tools used to design and implement applications. CASE tools are similar to and are partly inspired bycomputer-aided design(CAD) tools used for designing hardware products. CASE tools are intended to help develop high-quality, defect-free, and maintainab...
https://en.wikipedia.org/wiki/Computer-aided_software_engineering
This is a list of approaches, styles, methodologies, and philosophies in software development and engineering. It also containsprogramming paradigms,software development methodologies,software development processes, and single practices, principles, and laws. Some of the mentioned methods are more relevant to a specif...
https://en.wikipedia.org/wiki/List_of_software_development_philosophies
The followingoutlineis provided as an overview of and topical guide to software engineering: Software engineering– application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance ofsoftware; that is the application ofengineeringtosoftware.[1] The ACM Computing Classifica...
https://en.wikipedia.org/wiki/Outline_of_software_engineering
Software project managementis the process of planning and leading software projects.[1]It is a sub-discipline ofproject managementin whichsoftwareprojects are planned, implemented, monitored and controlled. In the 1970s and 1980s,the software industrygrew very quickly, as computer companies quickly recognized the rela...
https://en.wikipedia.org/wiki/Software_project_management
Software developmentis the process ofdesigningandimplementingasoftwaresolution tosatisfyauser. The process is more encompassing thanprogramming, writingcode, in that it includes conceiving the goal, evaluating feasibility, analyzingrequirements,design,testingandrelease. The process is part ofsoftware engineeringwhich a...
https://en.wikipedia.org/wiki/Software_development
Insoftware development,effort estimationis the process of predicting the most realistic amount of effort (expressed in terms of person-hours or money) required to develop or maintainsoftwarebased on incomplete, uncertain and noisy input. Effortestimatesmay be used as input to project plans, iteration plans, budgets, in...
https://en.wikipedia.org/wiki/Software_development_effort_estimation
Software documentationis written text or illustration that accompanies computersoftwareor is embedded in the source code. The documentation either explains how the software operates or how to use it, and may mean different things to people in different roles. Documentationis an important part of software engineering....
https://en.wikipedia.org/wiki/Software_documentation
Bottom-upandtop-downare strategies of composition and decomposition in fields as diverse asinformation processingand ordering knowledge,software,humanisticandscientific theories(seesystemics), and management and organization. In practice they can be seen as a style of thinking, teaching, or leadership. Atop-downapproa...
https://en.wikipedia.org/wiki/Top-down_and_bottom-up_design#Computer_science
User Account Control(UAC) is amandatory access controlenforcement feature introduced withMicrosoft'sWindows Vista[1]andWindows Server 2008operating systems, with a more relaxed[2]version also present inWindows 7,Windows Server 2008 R2,Windows 8,Windows Server 2012,Windows 8.1,Windows Server 2012 R2,Windows 10, andWindo...
https://en.wikipedia.org/wiki/User_Account_Control
Compartmentalization, ininformation security, whether public or private, is the limiting ofaccess to informationto persons or other entities on aneed-to-knowbasis to perform certain tasks. It originated in the handling ofclassified informationinmilitaryandintelligenceapplications. It dates back toantiquity, and was su...
https://en.wikipedia.org/wiki/Compartmentalization_(intelligence)
In software systems,encapsulationrefers to the bundling of data with the mechanisms or methods that operate on the data. It may also refer to the limiting of direct access to some of that data, such as an object's components.[1]Essentially, encapsulation prevents external code from being concerned with the internal wo...
https://en.wikipedia.org/wiki/Encapsulation_(object-oriented_programming)
The term "need to know" (alternatively spelledneed-to-know), when used bygovernmentsand other organizations (particularly those related tomilitary[1]orintelligence[2]), describes the restriction of data which is considered veryconfidentialandsensitive. Under need-to-know restrictions, even if one has all the necessary ...
https://en.wikipedia.org/wiki/Need_to_know
In computer security,privilege bracketingis a temporary increase insoftware privilegewithin a process to perform a specific function, assuming those necessary privileges at the last possible moment and dismissing them as soon as no longer strictly necessary, therefore ostensibly avoiding fallout from erroneous code tha...
https://en.wikipedia.org/wiki/Privilege_bracketing
Privilege escalationis the act of exploiting abug, adesign flaw, or a configuration oversight in anoperating systemorsoftware applicationto gain elevated access toresourcesthat are normally protected from an application oruser. The result is that an application or user with moreprivilegesthan intended by theapplication...
https://en.wikipedia.org/wiki/Privilege_escalation
Privilege revocationis the act of anentitygiving up some, or all of, theprivilegesthey possess, or someauthoritytaking those (privileged) rights away. Honoring thePrinciple of least privilegeat a granularity provided by the base system such assandboxingof (to that point successful) attacks to an unprivileged user acco...
https://en.wikipedia.org/wiki/Privilege_revocation_(computing)
Incomputer programmingandcomputer security,privilege separation(privsep) is one software-based technique for implementing theprinciple of least privilege.[1][2]With privilege separation, aprogramis divided into parts which are limited to the specificprivilegesthey require in order to perform a specific task. This is us...
https://en.wikipedia.org/wiki/Privilege_separation
Incomputer science,hierarchical protection domains,[1][2]often calledprotection rings, are mechanisms to protect data and functionality from faults (by improvingfault tolerance) and malicious behavior (by providingcomputer security). Computer operating systems provide different levels of access to resources. A protect...
https://en.wikipedia.org/wiki/Protection_ring
sudo(/suːduː/[4]) is ashellcommandonUnix-likeoperating systemsthat enables a user to run a program with the security privileges of another user, by default thesuperuser.[5]It originally stood for "superuser do",[6]as that was all it did, and this remains its most common usage;[7]however, the official Sudo project page ...
https://en.wikipedia.org/wiki/Sudo
Alphanumericalsoralphanumeric charactersare any collection of number characters and letters in a certainlanguage. Sometimes such characters may be mistaken one for the other. Merriam-Webstersuggests that the term "alphanumeric" may often additionally refer to other symbols, such as punctuation and mathematical symbols...
https://en.wikipedia.org/wiki/Alphanumeric_code
Anexploitis a method or piece of code that takes advantage ofvulnerabilitiesinsoftware,applications,networks,operating systems, orhardware, typically for malicious purposes. The term "exploit" derives from the English verb "to exploit," meaning "to use something to one’s own advantage." Exploits are designed to identif...
https://en.wikipedia.org/wiki/Exploit_(computer_security)
Shell shoveling, innetwork security, is the act ofredirectingtheinput and outputof ashellto a service so that it can be remotely accessed, aremote shell.[1] Incomputing, the most basic method of interfacing with the operating system is the shell. OnMicrosoft Windowsbased systems, this is a program calledcmd.exeorCOMMA...
https://en.wikipedia.org/wiki/Shell_shoveling
TheDOS APIis anAPIwhich originated with86-DOSand is used inMS-DOS/PC DOSand otherDOS-compatible operating systems. Most calls to the DOS API are invoked usingsoftware interrupt21h (INT21h). By calling INT 21h with a subfunction number in the AHprocessor registerand other parameters in other registers, various DOS serv...
https://en.wikipedia.org/wiki/DOS_API
TheLinux kernelprovides multiple interfaces touser-space and kernel-modecode. The interfaces can be classified as eitherapplication programming interface(API) orapplication binary interface(ABI), and they can be classified as either kernel–user space or kernel-internal. The Linux API includes the kernel–user space API...
https://en.wikipedia.org/wiki/Linux_kernel_API
vDSO(virtual dynamic shared object) is a kernel mechanism for exporting a carefully selected set ofkernel spaceroutines touser spaceapplications so that applications can call these kernel space routines in-process, without incurring the performance penalty of amode switchfromuser modetokernel modethat is inherent when ...
https://en.wikipedia.org/wiki/VDSO
Incomputer science, acall stackis astackdata structure that stores information about the activesubroutinesandinline blocksof acomputer program. This type of stack is also known as anexecution stack,program stack,control stack,run-time stack, ormachine stack, and is often shortened to simply the "stack". Although maint...
https://en.wikipedia.org/wiki/Call_stack
Incomputer programming, areturn statementcausesexecutionto leave the currentsubroutineand resume at the point in the code immediately after the instruction which called the subroutine, known as itsreturn address. The return address is saved by the calling routine, today usually on theprocess'scall stackor in aregister....
https://en.wikipedia.org/wiki/Return_address_(computing)
Automated theorem proving(also known asATPorautomated deduction) is a subfield ofautomated reasoningandmathematical logicdealing with provingmathematical theoremsbycomputer programs. Automated reasoning overmathematical proofwas a major motivating factor for the development ofcomputer science. While the roots of forma...
https://en.wikipedia.org/wiki/Automated_theorem_proving
Incomputer science,model checkingorproperty checkingis a method for checking whether afinite-state modelof a system meets a givenspecification(also known ascorrectness). This is typically associated withhardwareorsoftware systems, where the specification contains liveness requirements (such as avoidance oflivelock) as ...
https://en.wikipedia.org/wiki/Model_checking
This article listsmodel checkingtools and gives an overview of the functionality of each. The following table includes model checkers that have In the below table, the following abbreviations are used: There exists a few papers that systematically compare various model checkers on a common case study. The comparison...
https://en.wikipedia.org/wiki/List_of_model_checking_tools
Formal equivalence checkingprocess is a part ofelectronic design automation(EDA), commonly used during the development ofdigitalintegrated circuits, to formallyprovethat two representations of acircuit designexhibit exactly the same behavior. In general, there is a wide range of possible definitions of functional equi...
https://en.wikipedia.org/wiki/Formal_equivalence_checking
Incomputer scienceandmathematical logic, aproof assistantorinteractive theorem proveris a software tool to assist with the development offormal proofsby human–machine collaboration. This involves some sort of interactive proof editor, or otherinterface, with which a human can guide the search for proofs, the details of...
https://en.wikipedia.org/wiki/Proof_checker
Property Specification Language(PSL) is atemporal logicextendinglinear temporal logicwith a range of operators for both ease of expression and enhancement of expressive power. PSL makes an extensive use ofregular expressionsand syntactic sugaring. It is widely used in the hardware design and verification industry, wher...
https://en.wikipedia.org/wiki/Property_Specification_Language
Incomputer science,model checkingorproperty checkingis a method for checking whether afinite-state modelof a system meets a givenspecification(also known ascorrectness). This is typically associated withhardwareorsoftware systems, where the specification contains liveness requirements (such as avoidance oflivelock) as ...
https://en.wikipedia.org/wiki/Temporal_logic_in_finite-state_verification
Post-silicon validation and debugis the last step in the development of a semiconductorintegrated circuit. During the pre-silicon process, engineers test devices in a virtual environment with sophisticatedsimulation,emulation, andformal verificationtools. In contrast, post-silicon validation tests occur on actual dev...
https://en.wikipedia.org/wiki/Post-silicon_validation
Intelligent Verification, includingintelligent testbench automation, is a form offunctional verificationofelectronic hardwaredesigns used to verify that a design conforms to specification before device fabrication. Intelligent verification uses information derived from the design and specification(s) to expose bugs in ...
https://en.wikipedia.org/wiki/Intelligent_verification
Runtime verificationis a computing system analysis and execution approach based on extracting information from a running system and using it to detect and possibly react to observed behaviors satisfying or violating certain properties.[1]Some very particular properties, such asdataraceanddeadlockfreedom, are typically ...
https://en.wikipedia.org/wiki/Runtime_verification
Software verificationis a discipline ofsoftware engineering,programming languages, andtheory of computationwhose goal is to assure that software satisfies the expected requirements. A broad definition of verification makes it related tosoftware testing. In that case, there are two fundamental approaches to verificatio...
https://en.wikipedia.org/wiki/Software_verification
Electronic design automation(EDA), also referred to aselectronic computer-aided design(ECAD),[1]is a category ofsoftware toolsfor designingelectronic systemssuch asintegrated circuitsandprinted circuit boards. The tools work together in adesign flowthat chip designers use to design and analyze entiresemiconductorchips....
https://en.wikipedia.org/wiki/Hardware_verification
Cyclomatic complexityis asoftware metricused to indicate thecomplexity of a program. It is a quantitative measure of the number of linearly independentpathsthrough a program'ssource code. It was developed byThomas J. McCabe, Sr.in 1976. Cyclomatic complexity is computed using thecontrol-flow graphof the program. The n...
https://en.wikipedia.org/wiki/Cyclomatic_complexity
Linear code sequence and jump(LCSAJ), in the broad sense, is a software analysis method used to identify structural units in code under test. Its primary use is with dynamic software analysis to help answer the question "How much testing is enough?".[1]Dynamic software analysis is used to measure the quality and effic...
https://en.wikipedia.org/wiki/Linear_code_sequence_and_jump
Modified condition/decision coverage(MC/DC) is acode coveragecriterion used insoftware testing. MC/DC requires all of the below during testing:[1] Independence of a condition is shown by proving that only one condition changes at a time. MC/DC is used in avionics software development guidanceDO-178BandDO-178Cto ensu...
https://en.wikipedia.org/wiki/Modified_condition/decision_coverage
Mutation testing(ormutation analysisorprogram mutation) is used to design new software tests and evaluate the quality of existing software tests. Mutation testing involves modifying a program in small ways.[1]Each mutated version is called amutantand tests detect and reject mutants by causing the behaviour of the orig...
https://en.wikipedia.org/wiki/Mutation_testing
Regression testing(rarely,non-regression testing[1]) is re-runningfunctionalandnon-functional teststo ensure that previously developed and tested software still performs as expected after a change.[2]If not, that would be called aregression. Changes that may require regression testing includebugfixes, software enhance...
https://en.wikipedia.org/wiki/Regression_testing
Insoftware engineeringanddevelopment, asoftware metricis a standard of measure of a degree to which asoftware systemor process possesses some property.[1][2]Even if a metric is not a measurement (metrics are functions, while measurements are the numbers obtained by the application of metrics), often the two terms are u...
https://en.wikipedia.org/wiki/Software_metric
Java code coverage toolsare of two types: first, tools that add statements to theJavasource codeand require its recompilation. Second, tools that instrument thebytecode, either before or during execution. The goal is to find out which parts of the code are tested by registering the lines ofcode executedwhen running a t...
https://en.wikipedia.org/wiki/Java_code_coverage_tools
Inmathematics, aBézout domainis anintegral domainin which the sum of twoprincipal idealsis also a principal ideal. This means thatBézout's identityholds for every pair of elements, and that everyfinitely generated idealis principal. Bézout domains are a form ofPrüfer domain. Anyprincipal ideal domain(PID) is a Bézout ...
https://en.wikipedia.org/wiki/B%C3%A9zout_domain
Inmathematics, thelowest common denominatororleast common denominator(abbreviatedLCD) is thelowest common multipleof thedenominatorsof a set offractions. It simplifies adding, subtracting, and comparing fractions. The lowest commondenominatorof a set offractionsis the lowest number that is amultipleof all the denomina...
https://en.wikipedia.org/wiki/Lowest_common_denominator
Inmathematics, anatural numberais aunitary divisor(orHall divisor) of a numberbifais adivisorofband ifaandba{\displaystyle {\frac {b}{a}}}arecoprime, having no common factor other than 1. Equivalently, a divisoraofbis a unitary divisorif and only ifeveryprimefactor ofahas the samemultiplicityinaas it has inb. The conc...
https://en.wikipedia.org/wiki/Unitary_divisor
Inabstract algebra, thegroup isomorphism problemis thedecision problemof determining whether two givenfinite group presentationsrefer toisomorphicgroups. The isomorphism problem was formulated byMax Dehn,[1]and together with theword problemandconjugacy problem, is one of three fundamental decision problems in group th...
https://en.wikipedia.org/wiki/Group_isomorphism_problem
Channel capacity, inelectrical engineering,computer science, andinformation theory, is the theoretical maximum rate at whichinformationcan be reliably transmitted over acommunication channel. Following the terms of thenoisy-channel coding theorem, the channel capacity of a givenchannelis the highest information rate (...
https://en.wikipedia.org/wiki/Channel_capacity
Ininformation theory, thenoisy-channel coding theorem(sometimesShannon's theoremorShannon's limit), establishes that for any given degree of noise contamination of a communication channel, it is possible (in theory) to communicate discrete data (digitalinformation) nearly error-free up to a computable maximum rate thro...
https://en.wikipedia.org/wiki/Noisy_channel
Incoding theory,list decodingis an alternative to unique decoding oferror-correcting codesfor large error rates. The notion was proposed byEliasin the 1950s. The main idea behind list decoding is that the decoding algorithm instead of outputting a single possible message outputs a list of possibilities one of which is ...
https://en.wikipedia.org/wiki/List_decoding
Ingeometry, asphere packingis an arrangement of non-overlappingsphereswithin a containing space. The spheres considered are usually all of identical size, and the space is usually three-dimensionalEuclidean space. However, spherepacking problemscan be generalised to consider unequal spheres, spaces of other dimensions ...
https://en.wikipedia.org/wiki/Sphere_packing
Intelecommunication, aBerger codeis a unidirectionalerror detecting code, named after its inventor, J. M. Berger. Berger codes can detect all unidirectional errors. Unidirectional errors are errors that only flip ones into zeroes or only zeroes into ones, such as in asymmetric channels. Thecheck bitsof Berger codes are...
https://en.wikipedia.org/wiki/Berger_code
Incoding theory,burst error-correcting codesemploy methods of correctingburst errors, which are errors that occur in many consecutive bits rather than occurring in bits independently of each other. Many codes have been designed to correctrandom errors. Sometimes, however, channels may introduce errors which are locali...
https://en.wikipedia.org/wiki/Burst_error-correcting_code
Error correction code memory(ECC memory) is a type ofcomputer data storagethat uses anerror correction code[a](ECC) to detect and correctn-bitdata corruptionwhich occurs in memory. Typically, ECC memory maintains a memory system immune to single-bit errors: the data that is read from eachwordis always the same as the ...
https://en.wikipedia.org/wiki/ECC_memory
Link adaptation, comprisingadaptive coding and modulation(ACM) and others (such as Power Control), is a term used inwireless communicationsto denote the matching of themodulation,codingand othersignalandprotocolparameters to the conditions on theradio link(e.g. thepathloss, theinterferencedue to signals coming from oth...
https://en.wikipedia.org/wiki/Link_adaptation
Analgorithmis fundamentally a set of rules or defined procedures that is typically designed and used to solve a specific problem or a broad set of problems. Broadly, algorithms define process(es), sets of rules, or methodologies that are to be followed in calculations, data processing, data mining, pattern recognition...
https://en.wikipedia.org/wiki/List_of_algorithms#Error_detection_and_correction
Incoding theory,Hamming(7,4)is alinear error-correcting codethat encodes fourbitsof data into seven bits by adding threeparity bits. It is a member of a larger family ofHamming codes, but the termHamming codeoften refers to this specific code thatRichard W. Hammingintroduced in 1950. At the time, Hamming worked atBell ...
https://en.wikipedia.org/wiki/Hamming_code_(7,4)
Incoding theory,decodingis the process of translating received messages intocodewordsof a givencode. There have been many common methods of mapping messages to codewords. These are often used to recover messages sent over anoisy channel, such as abinary symmetric channel. C⊂F2n{\displaystyle C\subset \mathbb {F} _{2}^...
https://en.wikipedia.org/wiki/Decoding_methods
Inversive congruential generatorsare a type of nonlinear congruentialpseudorandom number generator, which use themodular multiplicative inverse(if it exists) to generate the next number in a sequence. The standard formula for an inversive congruential generator, modulo some primeqis: Such a generator is denoted symbol...
https://en.wikipedia.org/wiki/Inversive_congruential_generator
Incoding theory, theBose–Chaudhuri–Hocquenghem codes(BCH codes) form a class ofcyclicerror-correcting codesthat are constructed usingpolynomialsover afinite field(also called aGalois field). BCH codes were invented in 1959 by French mathematicianAlexis Hocquenghem, and independently in 1960 byRaj Chandra BoseandD. K. R...
https://en.wikipedia.org/wiki/BCH_code
TheBerlekamp–Massey algorithmis analgorithmthat will find the shortestlinear-feedback shift register(LFSR) for a given binary output sequence. The algorithm will also find theminimal polynomialof a linearlyrecurrent sequencein an arbitraryfield. The field requirement means that the Berlekamp–Massey algorithm requires ...
https://en.wikipedia.org/wiki/Berlekamp%E2%80%93Massey_algorithm
TheBerlekamp–Welch algorithm, also known as theWelch–Berlekamp algorithm, is named forElwyn R. BerlekampandLloyd R. Welch. This is a decoder algorithm that efficiently corrects errors inReed–Solomon codesfor an RS(n,k), code based on the Reed Solomon original view where a messagem1,⋯,mk{\displaystyle m_{1},\cdots ,m_{k...
https://en.wikipedia.org/wiki/Berlekamp%E2%80%93Welch_algorithm
Inabstract algebra, theChien search, named afterRobert Tienwen Chien, is a fast algorithm for determiningrootsofpolynomialsdefined over afinite field. Chien search is commonly used to find the roots of error-locator polynomials encountered in decodingReed-Solomon codesandBCH codes. The problem is to find the roots of ...
https://en.wikipedia.org/wiki/Chien_search
Incoding theory, acyclic codeis ablock code, where thecircular shiftsof each codeword gives another word that belongs to the code. They areerror-correcting codesthat have algebraic properties that are convenient for efficienterror detection and correction. LetC{\displaystyle {\mathcal {C}}}be alinear codeover afinite ...
https://en.wikipedia.org/wiki/Cyclic_code
Incoding theory,folded Reed–Solomon codesare likeReed–Solomon codes, which are obtained by mappingm{\displaystyle m}Reed–Solomon codewords over a larger alphabet by careful bundling of codeword symbols. Folded Reed–Solomon codes are also a special case ofParvaresh–Vardy codes. Using optimal parameters one can decode ...
https://en.wikipedia.org/wiki/Folded_Reed%E2%80%93Solomon_code
Incomputing,telecommunication,information theory, andcoding theory,forward error correction(FEC) orchannel coding[1][2][3]is a technique used forcontrolling errorsindata transmissionover unreliable or noisycommunication channels. The central idea is that the sender encodes the message in aredundantway, most often by u...
https://en.wikipedia.org/wiki/Forward_error_correction
In thecomputer sciencesubfield ofalgorithmic information theory, aChaitin constant(Chaitin omega number)[1]orhalting probabilityis areal numberthat, informally speaking, represents theprobabilitythat a randomly constructed program will halt. These numbers are formed from a construction due toGregory Chaitin. Although ...
https://en.wikipedia.org/wiki/Chaitin%27s_constant
Incomputer scienceandinformation theory, acanonical Huffman codeis a particular type ofHuffman codewith unique properties which allow it to be described in a very compact manner. Rather than storing the structure of the code tree explicitly, canonical Huffman codes are ordered in such a way that it suffices to only sto...
https://en.wikipedia.org/wiki/Canonical_Huffman_code
Incomputing,telecommunication,information theory, andcoding theory,forward error correction(FEC) orchannel coding[1][2][3]is a technique used forcontrolling errorsindata transmissionover unreliable or noisycommunication channels. The central idea is that the sender encodes the message in aredundantway, most often by u...
https://en.wikipedia.org/wiki/Channel_coding
Ininformation theory, theerror exponentof achannel codeorsource codeover the block length of the code is the rate at which the error probability decays exponentially with the block length of the code. Formally, it is defined as the limiting ratio of the negative logarithm of the error probability to the block length of...
https://en.wikipedia.org/wiki/Error_exponent
Ininformation theory, thenoisy-channel coding theorem(sometimesShannon's theoremorShannon's limit), establishes that for any given degree of noise contamination of a communication channel, it is possible (in theory) to communicate discrete data (digitalinformation) nearly error-free up to a computable maximum rate thro...
https://en.wikipedia.org/wiki/Noisy-channel_coding_theorem
Golomb codingis alossless data compressionmethod using a family ofdata compressioncodes invented bySolomon W. Golombin the 1960s. Alphabets following ageometric distributionwill have a Golomb code as an optimalprefix code,[1]making Golomb coding highly suitable for situations in which the occurrence of small values in...
https://en.wikipedia.org/wiki/Golomb_code
TheKruskal count[1][2](also known asKruskal's principle,[3][4][5][6][7]Dynkin–Kruskal count,[8]Dynkin's counting trick,[9]Dynkin's card trick,[10][11][12][13]coupling card trick[14][15][16]orshift coupling[10][11][12][13]) is aprobabilisticconcept originally demonstrated by the Russian mathematicianEvgenii Borisovich D...
https://en.wikipedia.org/wiki/Kruskal_count
Incomputer science, aninstruction set architecture(ISA) is anabstract modelthat generally defines howsoftwarecontrols theCPUin a computer or a family of computers.[1]A device or program that executes instructions described by that ISA, such as a central processing unit (CPU), is called animplementationof that ISA. In ...
https://en.wikipedia.org/wiki/Variable-length_instruction_set
Inmathematics, ameasure-preserving dynamical systemis an object of study in the abstract formulation ofdynamical systems, andergodic theoryin particular. Measure-preserving systems obey thePoincaré recurrence theorem, and are a special case ofconservative systems. They provide the formal, mathematical basis for a broad...
https://en.wikipedia.org/wiki/Metric_entropy
Themathematical theory of informationis based onprobability theoryandstatistics, and measures information with severalquantities of information. The choice of logarithmic base in the following formulae determines theunitofinformation entropythat is used. The most common unit of information is thebit, or more correctl...
https://en.wikipedia.org/wiki/Quantities_of_information
Brevity codesare used inamateur radio, maritime, aviation, police, and military communications. They are designed to convey complex information with a few words or codes. Some areclassifiedfrom the public.
https://en.wikipedia.org/wiki/Brevity_code
Ten-codes, officially known asten signals, arebrevity codesused to represent common phrases in voice communication, particularly by US public safety officials and incitizens band(CB) radio transmissions. The police version of ten-codes is officially known as theAPCO Project 14 Aural Brevity Code.[1] The codes, develop...
https://en.wikipedia.org/wiki/Ten-code
Acrossword(orcrossword puzzle) is aword gameconsisting of a grid of black and white squares, into which solvers enter words or phrases ("entries") crossing each other horizontally ("across") and vertically ("down") according to a set of clues. Each white square is typically filled with one letter, while the black squar...
https://en.wikipedia.org/wiki/Cipher_crossword
Apasswordis a word, phrase or string of characters used to gain access to a resource, such as an object, area or information. Passwordmay also refer to:
https://en.wikipedia.org/wiki/Password_(disambiguation)
Asafewordis a code word or signal used to communicate personal states or limits regarding physical, emotional, or moral boundaries. Safewordmay also refer to:
https://en.wikipedia.org/wiki/Safeword_(disambiguation)
Inmathematics, anabsorbing element(orannihilating element) is a special type of element of asetwith respect to abinary operationon that set. The result of combining an absorbing element with any element of the set is the absorbing element itself. Insemigrouptheory, the absorbing element is called azero element[1][2]be...
https://en.wikipedia.org/wiki/Absorbing_element
In mathematics, theadditive inverseof anelementx, denoted−x,[1]is the element that whenaddedtox, yields theadditive identity,0 (zero).[2]In the most familiar cases, this is thenumber0, but it can also refer to a more generalizedzero element. Inelementary mathematics, the additive inverse is often referred to as theopp...
https://en.wikipedia.org/wiki/Additive_inverse
Inmathematics, and in particular,algebra, ageneralized inverse(or,g-inverse) of an elementxis an elementythat has some properties of aninverse elementbut not necessarily all of them. The purpose of constructing a generalized inverse of a matrix is to obtain a matrix that can serve as an inverse in some sense for a wide...
https://en.wikipedia.org/wiki/Generalized_inverse
Inmathematics, anidentityis anequalityrelating onemathematical expressionAto another mathematical expressionB, such thatAandB(which might contain somevariables) produce the same value for all values of the variables within a certaindomain of discourse.[1][2]In other words,A=Bis an identity ifAandBdefine the samefunctio...
https://en.wikipedia.org/wiki/Identity_(mathematics)
Inmathematics, anidentity function, also called anidentity relation,identity maporidentity transformation, is afunctionthat always returns the value that was used as itsargument, unchanged. That is, whenfis the identity function, theequalityf(x) =xis true for all values ofxto whichfcan be applied. Formally, ifXis aset...
https://en.wikipedia.org/wiki/Identity_function
Inmathematics, the concept of aninverse elementgeneralises the concepts ofopposite(−x) andreciprocal(1/x) of numbers. Given anoperationdenoted here∗, and anidentity elementdenotede, ifx∗y=e, one says thatxis aleft inverseofy, and thatyis aright inverseofx. (An identity element is an element such thatx*e=xande*y=yfor a...
https://en.wikipedia.org/wiki/Inverse_element
Inmathematics, and more specifically inabstract algebra, apseudo-ringis one of the following variants of aring: None of these definitions are equivalent, so it is best[editorializing]to avoid the term "pseudo-ring" or to clarify which meaning is intended. Thisalgebra-related article is astub. You can help Wikipedia b...
https://en.wikipedia.org/wiki/Pseudo-ring#Properties_weaker_than_having_an_identity
Unitalmay refer to:
https://en.wikipedia.org/wiki/Unital_(disambiguation)
Inmathematics,anticommutativityis a specific property of some non-commutativemathematicaloperations. Swapping the position oftwo argumentsof an antisymmetric operation yields a result which is theinverseof the result with unswapped arguments. The notioninverserefers to agroup structureon the operation'scodomain, possib...
https://en.wikipedia.org/wiki/Anticommutative_property
Inquantum mechanics, thecanonical commutation relationis the fundamental relation betweencanonical conjugatequantities (quantities which are related by definition such that one is theFourier transformof another). For example,[x^,p^x]=iℏI{\displaystyle [{\hat {x}},{\hat {p}}_{x}]=i\hbar \mathbb {I} } between the positi...
https://en.wikipedia.org/wiki/Canonical_commutation_relation
Inmathematics, especiallygroup theory, thecentralizer(also calledcommutant[1][2]) of asubsetSin agroupGis the setCG⁡(S){\displaystyle \operatorname {C} _{G}(S)}of elements ofGthatcommutewith every element ofS, or equivalently, the set of elementsg∈G{\displaystyle g\in G}such thatconjugationbyg{\displaystyle g}leaves ea...
https://en.wikipedia.org/wiki/Centralizer