Wiktionarypar variable wikiversity Variable may refer to Variable research , a logical set of attributes Variable mathematics , a symbol that represents a quantity in an algebraic expression. Variable programming , a symbolic name associated with a value and whose associated value may be changed Variable star , a type of star as in astronomical object Dependent and independent variables in statistics disambig Category Variables ca Variable de Variable el eu Aldagai argipena fa fr Variable it Variabile ja pl Zmienna pt Vari vel sk Premenn sr fi Muuttuja ... more details
Infobox television episode Title The Variable Series Lost TV series Lost Image Caption Season 5 Episode ... List of Lost episodes Prev Some Like It Hoth Next Follow the Leader Lost Follow the Leader The Variable ... directly with the concept of time travel . The Variable also features the death of Daniel, portrayed ... title Lost Episode Recaps The Variable publisher American Broadcasting Company accessdate April ... File Lindelof y Cuse.jpg 350px thumb Damon Lindelof and Carlton Cuse , the show runner s of Lost The Variable ... name n&o In The Variable , the viewers would get a few more pieces of the puzzle, Lindelof said, and added ... Access Hollywood accessdate 2009 05 04 ref The Variable was the hundredth episode of the show to be produced ... in the episode. The Variable was watched live or recorded and watched within five hours of broadcast .... ref cite web url http tv.ign.com articles 978 978209p1.html title Lost The Variable Review last Carabott ... eyes, we decided to forgive him. But The Variable showed us the dynamic at the heart of Daniel s stuttering ... www.pastemagazine.com blogs tv detail 2009 04 lost review the variable episode 514.html title Lost Review The Variable last Dovey first Rachel date April 30, 2009 work Paste accessdate 2009 05 10 ref ... that Lost had been too slow lately, here you go. Those who watched The Variable saw more action ... Review Lost The Variable last Sweeney first Adam date May 1, 2009 publisher Film School Rejects accessdate ... quotTHE VARIABLEquot Page1.html title Thud Review Lost The Variable last Oliver first David date ... 2009 04 30 lost 514 the variable title LOST 5.14 The Variable last Lackey first Stephen date ... s parents. ref cite web url http www.airlockalpha.com news426311.html title Lost The Variable ... cite web url http tvoholic.com episode reviews lost the variable title Lost The Variable first ... said that as an internal character piece, The Variable was not so much a great ending for Daniel ... www.tvovermind.com tv news lost lost the variable lose a geek gain a plan 3912 title LOST The Variable ... more details
The term dummy variable can refer to either of the following Bound variable &ndash in mathematics and computer science, a placeholder variable Dummy variable statistics &ndash an indicator variable. disambig ... more details
In object Oriented programming a member variable sometimes called a member Field computer science field is a variable programming variable that is associated with a specific Class computer science class , and accessible for all its method computer science methods . If there is only one copy of the variable shared with all instances of the class it is called a class variable or static member variable. If each instance of the class has its own copy of the variable, it is called instance variable . See also Global variable Local variable Category Object oriented programming Category Variable computer programming Compu prog stub ... more details
In computer programming , variable shadowing occurs when a variable declared within a certain scope decision block, method, or inner class has the same name as a variable declared in an outer scope. This outer variable is said to be shadowed. This can lead to confusion, as it may be unclear which variable subsequent uses of the shadowed variable name refer to. One of the first languages to introduce variable shadowing was ALGOL , which first introduced blocks to establish scopes. It was also permitted by many of the derivative programming languages including C and Java programming language Java . The C Sharp programming language C language breaks this tradition, allowing variable shadowing between an inner and an outer class, and between a method and its containing class, but not between an if block and its containing method, or between case statements in a Switch statement switch block. Example The following Java programming language Java code provides an example of variable shadowing. source lang java class VariableShadowing static int x 1 public static void main String args This local variable shadows the class variable int x 100 This statement prints the local variable System.out.println Local variable x x 100 This statement prints the shadowed variable System.out.println Class variable x VariableShadowing.x 1 source See also Overloading Type polymorphism Category Variable computer programming ... more details
In statistics and social sciences , an antecedent variable is a Variable mathematics variable that can help to explain the apparent relationship or part of the relationship between other variables that are nominally in a Causality cause and effect relationship. In a regression analysis , an antecedent variable would be one that influences both the independent variable and the dependent variable . See also Path analysis statistics Latent variable Intervening variable References Olobatuyi M.E. 2006 A user s guide to path analysis , University Press of America. ISBN 0761832300 Chapter 2 Category Statistical terminology Category Regression analysis Category Statistical dependence Category Design of experiments stats stub ... more details
Unreferenced date December 2009 Orphan date February 2009 In computer programming a singleton variable is a variable programming variable that is referred to only once after it has been declared. Examples of where a variable might only be referenced once is as a dummy argument in a function call , or when its address is assigned to another variable which subsequently accesses its allocated storage. This usage pattern sometimes occurs because a mistake has been made, with more than one reference being intended. Some compiler s and Lint programming tool lint like tools flag occurrences of singleton variables. See also Singleton pattern DEFAULTSORT Singleton Variable Category Variable computer programming ... more details
Variable skink may denote either of two different skink s Eumeces multivirgatus epipleurotus , the southern subspecies of the Many lined Skink from North America Trachylepis varia , the Variable Mabuya from Africa dab ... more details
Unreferenced date February 2007 orphan date November 2009 An unreferenced variable in the source code of a computer program is a Variable programming variable that is defined but which is never used. This may result in a harmless waste of memory unless the compiler used detects the situation and does not allocate storage for the variable, perhaps also issuing a warning . Some coding style coding guideline documents consider an unreferenced variable to be a symptom of a potential coding fault. Examples C programming language C source lang c int main void int i, j for i 0 i 10 i printf d , i return 0 source In this example, j is an unreferenced variable. DEFAULTSORT Unreferenced Variable Category Variable computer programming Compu prog stub ... more details
Variable geometry may refer to Various different ways to alter the shape of an aircraft s wings in flight in order to alter their aerodynamic properties Variable sweep wing s or swing wings , variable camber wing s, variable incidence wing s, and Oblique wing s. Multi speed Europe , a proposed strategy for European integration disambig Long comment to avoid being listed on short pages ... more details
Unreferenced date December 2007 For the notion of a controlled variable, see independent variable . The term control variable has different meanings, depending on the area in which it is used. The control variable is something that is constant and unchanged in an experiment. In scientific experimentation, a control variable is a one that must not be changed throughout an experiment because it affects the dependent variables and thus affects the outcome of the experiment. For example, in the experimental verification of Boyles law, the temperature must be kept constant. Essentially, a controlled variable is what is kept the same throughout the experiment. An example of a controlled variable would be if you have experimented on plants and tested a product on two plants, the soil and the pot would be two controlled variables. A control variable is any factor that remains unchanged and strongly influences values also a factor held constant to test the relative impact of an independent variable. Control theory In control theory , control variables are the variables that are input to the control system. Reaction rate is the dependent variable and everything else that can change the reaction rate must be controlled kept constant so that you only measure the effects of concentration. Variables that need to be controlled in this case include temperature, catalyst, surface area of solids, and pressure. If not controlled, they complicate the experiment and hence, the test is less valid. For example, a control variable could be time or mass or each marble had ten minutes to dissolve in acid. Computer Programming In Computer programming , a control variable is a program variable that is used ... variable is used to regulate the number of times the body of a program loop is executed it is incremented or decremented when counting down each time the loop body is executed. a single control variable ... simple Control variable ... more details
Image Ngc2261.jpg right 300px thumb A Hubble Space Telescope image of NGC 2261 , a classic example of a variable nebula. Variable nebulae are reflection nebula reflection nebulae that change in brightness because of changes in their star. See also NGC 1555 NGC 2261 Category Reflection nebulae Category Nebulae nebula stub es Nebulosa variable it Nebulosa variabile ru simple Variable nebula tr De i en bulutsu vi Tinh v n bi n quang zh ... more details
In type theory and programming language s, a type variable is a Variable mathematics mathematical variable ranging over data types types . Even in programming languages that allow variable programming mutable variable s, a type variable remains an abstraction, in the sense that it does not correspond to some memory locations. Programming language s that support parametric polymorphism make use of universally quantified type variables. Languages that support existential type s make use of existentially quantified type variables. For example, the following OCaml code defines a polymorphic identity function that has a universally quantified type, which is printed by the interpreter on the 2nd line let id x x val id a a fun In mathematical notation, the type of the function code id code is math forall a.a to a math , where a is a type variable. See also System F type theory stub Category Functional programming pl Zmienna typowa ... more details
Unreferenced date December 2009 Cleanup rewrite date February 2010 In object oriented programming with Class computer science class es, an instance variable is a variable programming variable defined in a class i.e. a member variable , for which each Object computer science object of the class has a separate copy. They live in memory for the life of the object. An instance variable is the opposite of class variable , and it is a special type of instance member . An example of an instance variable is private double length Technically speaking, instance variables are objects stored in individual states in non static fields , that is, fields declared without the static keyword. Non static fields are also known as instance variables because their values are unique to each instance of a class to each object, in other words the currentSpeed of one bicycle is independent from the currentSpeed of another. Simper definition is instance variables are things an object knows about itself. ....... DEFAULTSORT Instance Variable Category Object oriented programming Category Variable computer programming Compu prog stub es Variable de instancia it Variabile di istanza ja ... more details
Three ships of the Royal Navy have borne the name HMS Variable HMS Variable 1808 6 was a 12 gun sloop schooner , previously the civilian ship Redbridge . She was purchased in 1808, and removed from the Navy List in 1814. HMS Variable 1814 6 was a 14 gun schooner, previously the civilian ship Edward . She was purchased in 1814 and broken up in 1817. HMS Variable 1827 6 was a 10 gun Cherokee class brig sloop Cherokee class brig sloop launched in 1827. She was renamed HMS Pigeon and converted to a 6 gun packet ship packet brig in 1829 and was ordered to be sold in 1847. Shipindex DEFAULTSORT Variable, Hms Category Royal Navy ship names ... more details
In computer programming , a static variable is a variable programming variable that has been static memory allocation allocated statically whose object lifetime lifetime extends across the entire run of the program. This is in contrast to the more ephemeral automatic variable s local variables , whose storage is allocated and deallocated on the call stack and in contrast to objects whose storage is dynamic memory allocation dynamically allocated . In many programming languages, such as Pascal programming language Pascal , all local variable s are automatic variable automatic and all global variable s are allocated statically. In these languages, the term static variable is generally not used, since local and global suffice to cover all the possibilities. C and related languages In the C programming language C programming language and its close descendants such as C and Objective C , code static code is a storage class not to be confused with object oriented programming Class classes in object oriented programming , along with code auto code for automatic variables , code register code a variant of code auto code and code extern code for static variables and functions which are visible in other source files . Every variable in a C program is in exactly one of these storage classes. Every C variable declared as code static code has static lifetime and is not visible outside its own translation unit programming translation unit . There are other effects depending on where the variable ... scope . Local variable Static local variables Static local variables variables declared as code static code inside a function are statically allocated while having the same scope as automatic variable ... in C , member variables declared as code static code inside class definitions are class variable s shared between all class instances, as opposed to instance variable s . See also Global variable Thread ... Stroustrup Addison Wesley, 2000 ISBN 0 201 70073 5 Category Variable computer programming es Variable ... more details
Controlling for a variable refers to the deliberate varying of the experiment al conditions in order to see the impact of a specific Variable mathematics variable when predicting the outcome variable see independent and dependent variables . Controlling tends to reduce the errors and residuals in statistics experimental error . A control is something that does not change in the experiment. Controlling for a variable is also a term used in statistics statistical data analysis when inferences may need to be made for the relationships within one set of variables given that some of the inter relations may derive from relations to variables in another set. This is broadly equivalent to conditioning on the variables in the second set, although only linear relations may be taken into account. Such analyses may be described as controlling for variable X , or controlling for the variations in X . See also Scientific control References http www.stat.sdu.dk matstat Design index.html Experimental Design FAQ Category Statistical terminology Category Design of experiments Category Regression analysis Stat stub ... more details
BY Draconis variables are main sequence variable star s of stellar classification late spectral types , usually K or M. The name comes from the archetype for this category of variable star system, BY Draconis . They exhibit variations in their luminosity due to rotation of the star coupled with star spot s, and other chromosphere chromospheric activity. ref name MLM cite journal author Lopez Morales, Mercedes Morrell, N. I. Butler, R. P. Seager, S. title Limits to Transits of the Neptune mass planet orbiting Gl 581 journal Publications of the Astronomical Society of the Pacific year 2006 volume 118 pages arxiv astro ph 0609255 quote BY Draconis variable. This type of variable is characterized by quasiperiodic photometric variations over time scales from less than a day to months, and amplitudes ranging from a few hundredths of a magnitude to 0.5 mags. ref Resultant brightness fluctuations are generally less than 0.5 Apparent magnitude magnitudes ref name MLM on timescales equivalent to the star s rotational period, typically from a fraction of a day to several months. Some of these stars may also have flares, resulting in additional variations of the UV Ceti variable UV Ceti type . Oddly enough, Procyon the 8th brightest night time star which is an F5 sub giant or dwarf has also been classified as a BY Draconis variable. Source Schaaf, The Brightest Stars , Wiley, 2008. References reflist Samus N.N., Durlevich O.V., et al. Combined General Catalog of Variable Stars GCVS4.2, 2004 Ed. Schaaf, Fred, The Brightest Stars , Wiley, 2008 Variable star topics DEFAULTSORT By Draconis Variable Category BY Draconis variables Category Variable stars var star stub ca Variable BY Draconis de BY Draconis Stern es Estrella variable BY Draconis fr Variable de type BY Draconis it Variabile BY Draconis ja BY ru BY fi BY Draconis muuttuja tr BY Draconis de i eni zh BY ... more details
Unreferenced date December 2009 In computer programming , a temporary variable is a variable programming variable whose purpose is short lived, usually to hold temporarily data that will soon be discarded, or before it can be placed at a more permanent Memory computers memory location. Because it is short lived, it is usually declared with local Scope programming scope . There is no formal definition of what makes a variable temporary , but it is an often used term in programming. A typical example would be that of swap computer science swapping the contents of two variables. To swap the contents of variables a and b one would typically use a temporary variable temp as follows, so as to preserve the data from a as it is being overwritten by b temp a a b b temp Temporary variables are Naming conventions programming usually named with identifier s that abbreviation abbreviate the word temporary , such as temp , tmp or simply t , or with common metasyntactic variable names, the most common of which are foo , bar , baz see also foobar . The letters i , j , k and so on are also frequently used for index information technology Array element identifier indices , a tradition stemming from early Fortran and mathematics. See also Temporary folder Temporary file Temporary filesystem DEFAULTSORT Temporary Variable Category Variable computer programming pt Vari vel tempor ria computa o ru ... more details
In statistics , observable variables or manifest variables , as opposed to latent variable s, are those Variable mathematics variables that can be observed and directly measured. ref Dodge, Y. 2003 The Oxford Dictionary of Statistical Terms , OUP. ISBN 0 19 920613 9 ref See also Observables in physics Observability in control theory Latent variable model References references Category Social sciences Category Econometrics Category Statistical terminology Econometrics stub statistics stub ... more details
practice precisely because of their non locality a global variable can potentially be modified from ... William Wulf and Mary Shaw, Global Variable Considered Harmful , ACM SIGPLAN Notices, volume 8, issue 2, 1973 February, pp. 28 34. ref A global variable therefore has an unlimited potential for creating ... a variable outside all functions see below . However, such a variable should be called external ... files, the variable will only be accessible from those modules where it is declared again ... variable in C programming language C source lang c Note that this example is correct. global does not qualify as a global variable as it is not in scope everywhere . include stdio.h int global 3 This is the external variable. static void ChangeGlobal void global 5 Reference to external variable in a function. int main void printf d n , global Reference to external variable in another function. ChangeGlobal printf d n , global return 0 source As the variable is an external one, there is no need .... Since any code anywhere in the program can change the value of the variable at any time, understanding the use of the variable may entail understanding a large portion of the program. They make ... a global variable makes a name dangerous to use for any other local or object scope variable. A local variable of the same name can shield the global variable from access, again leading to harder to understand code. The setting of a global variable can create side effects that are hard to understand ... in other languages because of their similar sharing behavior. See also Variable programming Variables Static variable External variable Singleton pattern Local variable References references Category Variable computer programming de Globale Variable es Variable global fr Variable globale ko ja ... more details
In the C programming language, an external variable is a variable defined outside any function block. On the other hand, a local automatic variable is a variable defined inside a function block. quote ... keyword, it is necessary to know the difference between defining and declaring a variable. When you define a variable, you are telling the compiler to allocate memory for that variable, and possibly also to initialize its contents to some value. When you declare a variable, you are telling the compiler that the variable was defined elsewhere. You are just telling the compiler that a variable by that name ... declare a variable, or to force a declaration without a definition. It is also possible to explicitly define a variable, i.e. to force a definition. It is done by assigning an initialization value to a variable. If neither the extern keyword nor an initialization value are present, the statement ... and decide. A variable must be defined once in one of the modules of the program. If there is no definition or more than one, an error is produced, possibly in the linking stage. A variable may ... variable may also be declared inside a function. In this case you must use the extern keyword, otherwise the compiler will consider it a definition of a local variable, which has a different ... variable must be defined, exactly once, outside of any function this sets aside storage for it. The variable ... of the variable. The declaration may be an explicit extern statement or may be implicit from context ... to external variables in this section. Definition refers to the place where the variable is created or assigned storage declaration refers to places where the nature of the variable is stated but no storage ... keyword An external variable can be accessed by all the functions in all the modules of a program. It is a global variable. For a function to be able to use the variable, a declaration or the definition of the external variable must lie before the function definition in the source code ... more details
Image CVP TC FC VC.svg thumb right 240px Decomposing Total Costs as Fixed Costs plus Variable cost Variable Costs . Variable costs are expenses that change in proportion to the activity of a business. ref name GNB pp 48 Garrison, Noreen, Brewer. Ch 2 Managerial Accounting and Costs Concepts, pp 48 ref Variable cost is the sum of marginal cost s over all units produced. It can also be considered normal costs. Fixed cost s and variable costs make up the two components of total cost . Direct Costs , however, are costs that can easily be associated with a particular cost object . ref name GNB pp 51 Garrison, Noreen, Brewer. Ch 2 Managerial Accounting and Costs Concepts, pp 51 ref However, not all variable costs are direct costs. For example, variable manufacturing Overhead business overhead costs are variable costs that are indirect costs , not direct costs. Variable costs are sometimes called unit level costs as they vary with the number of units produced. Direct labor and overhead are often called conversion cost , ref name GNB pp 39 Garrison, Noreen, Brewer. Ch 2 Managerial Accounting and Costs Concepts, pp 39 ref while direct material and direct labor are often referred to as prime ... in expenses happen with little or no need for managerial intervention. These costs are variable costs ..., and so the more electricity gets used. This extra spending can therefore be regarded as variable. In retail the cost of goods is almost entirely a variable cost this is not true of manufacturing ... a variable cost. For some employees, salary is paid on monthly rates, independent of how many hours ... be varied, so this type of labour cost is a variable cost. See also Multicol Cost Cost accounting Cost curve Cost driver Multicol break Semi variable cost Fixed cost Total cost Contribution margin ... Costs Category Management accounting Category Production economics ar ca Cost variable cs Variabiln n klady de Variable Kosten es Costo variable eu Kostu aldakor fr Co t proportionnel ... more details
In object oriented programming with Class computer science class es, a class variable is a Variable programming variable defined in a class i.e. a member variable of which a single copy exists, regardless of how many Instance computer science instance s of the class exist. ref name TheJavaTurotialVariables cite web url http download.oracle.com javase tutorial java nutsandbolts variables.html title The Java Tutorial, Variables accessdate 2010 10 21 ref ref name TheJavaTutorialUnderstandingInstanceAndClassMembers cite web url http download.oracle.com javase tutorial java javaOO classvars.html title The Java Tutorial, Understanding Instance and Class Members accessdate 2010 10 21 ref ref name ThePythonLanguageReferenceCompoundStatements cite web url http docs.python.org reference compound stmts.html class definitions title The Python Language Reference, Compound Statements accessdate 2010 10 21 ref ref name ObjectiveCRuntimeReference cite web url http developer.apple.com library mac documentation Cocoa Reference ObjCRuntimeRef Reference reference.html title Objective C Runtime Reference accessdate 2010 10 21 ref A class variable is the opposite of an instance variable . It is a special type of Class computer science Structure class attribute or class property, field, or data member . In Java programming language Java , C Sharp programming language C , and C , class variables are declared with the keyword computer programming keyword code static code , and may therefore be referred ... number Request number count modifies the instance variable this number count modifies the class variable Request count int Request count 0 source In this C example, the class variable code Request count ... object is given a code number code in sequential order. Since code count code is a class variable ... own distinct code number code field. Notes Reflist 2 DEFAULTSORT Class Variable Category Object oriented programming Category Variable computer programming es Variable de clase ja ... more details
unreferenced date November 2009 In computer programming , a variable is a symbolic name given to some ... of the information it represents. A variable name in computer source code is usually associated ... of Variable mathematics variables in mathematics . The value of a computing variable is not necessarily part of an equation or formula as in mathematics. In computing, a variable may be employed in a repetitive ... with the actual locations of the data. While the variable name, type, and location generally remain fixed, the data stored in the location may alter during program execution. Identifiers referencing a variable An identifier referencing a variable can be used to access the variable in order to read out the value, or alter the value, or modify the Attribute computing attributes of the variable, such as access ..., a variable might be referenced by the identifier code total count code and the variable can contain the number 1956. If the same variable is referenced by the identifier code x code as well, and if using this identifier code x code , the value of the variable is altered to 2009, then reading ... programming language a variable can only be referenced by a single identifier, that can simply be called the name of the variable . Otherwise we can talk about one of the names of the variable . For instance, in the previous example, the code total count code is a name of the variable in question, and code x code is another name of the same variable. Actions on a variable In imperative programming ... variable to store anything supported by the programming language. Naming conventions Main Naming ... the format of valid identifiers. In almost all languages, variable names cannot start with a digit ... in variable names varies from language to language many languages only permit the underscore in variable ... characters known as sigil computer programming sigil s are prefixed or appended to variable identifiers to indicate the variable s type. Case sensitivity of variable names also varies between ... more details
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