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 computer science , 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 bg ca Variable de Variable el es Variable desambiguaci n eu Aldagai argipena fa fr Variable it Variabile ja pl Zmienna pt Vari vel sk Premenn ckb 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 ... abc.go.com primetime lost index?pn recap t 162212&d 191111 title Lost Episode Recaps The Variable publisher ... Lindelof and Carlton Cuse , the show runner s of Lost The Variable was written by Edward Kitsis and Adam .... ref name n&o In The Variable , the viewers would get a few more pieces of the puzzle, Lindelof ..., 2009 work Access Hollywood accessdate 2009 05 04 ref The Variable was the hundredth episode of the show ... 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 node 6311 title Lost The Variable last ... lost the variable title Lost The Variable first Fred date April 30, 2009 publisher TVoholic.com accessdate 2009 05 10 ref Jon Lachonis of TVOvermind said that as an internal character piece, The Variable ... to who Daniel truly was. ref cite web url http www.tvovermind.com tv news lost 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, the variable is called an instance variable . ref cite web accessdate 2011 08 12 author Richard G. Baldwin date 1999 03 10 location http www.dickbaldwin.com publisher Richard G Baldwin Programming Tutorials title Q What is a member variable? quote A member variable is a member of a class class variable or a member of an object instantiated from that class instance variable . It must be declared within a class, but not within the body of a method of the class. url http www.dickbaldwin.com java Java020.htm ref References Reflist 2 See also Global variable Local variable Category Object oriented programming Category Variable computer programming Compu prog 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. 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. Singleton variables sometimes occur because a mistake has been made such as assigning a value to a variable and forgetting to use it later, or mistyping one instance of the variable name. 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
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 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
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 contrasts with a class variable , and it is a special type of instance member . An example C or Java declaration of an instance variable is br 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 code currentSpeed code of one bicycle is independent from the code currentSpeed code of another. A simpler definition is that instance variables are things an object knows about itself. A typical declaration in Objective C would look like interface CustomClassName NSObject NSString ivar DEFAULTSORT Instance Variable Category Object oriented programming Category Variable computer programming Compu prog stub es Variable de instancia fr Variable d instance it Variabile di istanza ja ... 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
Variable geometry may refer to Variable geometry ways to alter the shape of an aircraft s wings in flight in order to alter their aerodynamic properties 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 The term control variable has different meanings, depending on the area place in which it is used. The control variable is something that is constant and unchanged in an experiment. A control variable is any factor that remains unchanged and strongly influences values it is held constant to test the relative impact of an independent variable . In scientific experimentation, a control variable is the one that must not be changed throughout an experiment because it affects the independent variables and thus affects the outcome of the experiment. For example, in the experimental verification of Boyle s 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. Control theory In control theory , controlled 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 the analyst can 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 to regulate the flow of control of the program. Examples A Infinite loop Looping loop control variable is used to regulate the number of times ... the loop body is executed. A single control variable can identify the present State computer science state of a computer program . Category Experiments ca Variable de control simple Control variable ... 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
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 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
In a scientific experiment measuring the effect of one or more independent variable s on a dependent variable, controlling for a variable is a method to reduce the confounding effect of variations in a third variable that may also affect the value of the dependent variable. For example, in an experiment to determine the effect of nutrition the independent variable on organism growth the dependent variable , the age of the organism the third variable needs to be controlled for, since the effect may also depend on the age of an individual organism. To a certain extent, systematic selection bias can be avoided, and the further confounding effect can be reduced, by a random assignment of individuals to the experimental group and the control group , but controlling tends to reduce the errors and residuals in statistics experimental error further. The essence of the method is to ensure that comparisons between the control group and the experimental group are only made for groups or subgroups for which the variable to be controlled has as much as possible the same statistical distribution . A common way to achieve this is to Partition of a set partition the groups into subgroups whose members have nearly the same value for the controlled variable. 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 probability conditioning on the variables in the second set, although in some techniques 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 ... 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 temporary 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 Array data structure 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 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 ... defining and declaring a variable. When a variable is defined , the compiler allocates memory for that variable and possibly also initializes its contents to some value. When a variable is declared , the compiler requires that the variable be defined elsewhere. The declaration informs the compiler that a variable by that name and type exists, but the compiler need not allocate memory for it since ... words, it is a way to explicitly 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 code extern code keyword nor an initialization ... to analyse the modules of the program and decide. A variable must be defined once in one ... in the linking stage. A variable may be declared many times, as long as the declarations are consistent ... variable may also be declared inside a function. In this case the code extern code keyword must be used, otherwise the compiler will consider it a definition of a local variable, which has a different ... to be defined inside a function. quote An external variable must be defined, exactly once, outside of any function this sets aside storage for it. The variable must also be declared in each function that wants to access it this states the type of the variable. The declaration may be an explicit ... 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 is allocated. The C Programming Language ... 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 ... 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. Static variables are global, and in languages that do make the distinction between global and static variables, both are typically allocated ... extern code , code auto code and code register code which are also reserved words . Every variable ... unit only code auto code , code register code automatic variable function call none In these languages, the term static variable has two meanings which are easy to confuse Language independent A variable with the same lifetime as the program, as described above or C family specific A variable ... but not the second. As well as specifying static lifetime, declaring a variable as code static ... . 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 automatic ... 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 Thread local storage Variable programming , especially Variable programming Scope and extent Scope and extent References The C ... 0 201 70073 5 Category Memory management Category Variable computer programming es Variable est tica ... more details
about the engineering indicator the mathematical concept used in thermodynamics process function A process variable , process value or process parameter is the current status of a process under control. An example of this would be the temperature of a furnace. The current temperature is called the process variable, while the desired temperature is known as the setpoint control system set point . Measurement of process variables are important in controlling a process. The process variable is a dynamic feature of the process which may change rapidly. Accurate measurement of process variables is important for the maintenance of accuracy in a process. There are four commonly measured variables which affect chemical and physical process pressure , Thermodynamic temperature temperature , level and flow. cn date December 2011 Tech stub DEFAULTSORT Process Variable Category Control theory ... 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 hr Promjenljiva maglica it Nebulosa variabile ru simple Variable nebula tr De i en bulutsu vi Tinh v n bi n quang zh ... more details
Hidden variables may refer to Hidden variable theory Hidden variable theories , in physics a class of theories trying to explain away the statistical nature of quantum mechanics Latent variable s, in statistics, variables that are inferred from other observed variables Hidden transformation , in computer science, a way to transform a generic constraint satisfaction problem into a binary one by introducing new hidden variables Confounding or hidden variables in general. That is, a variable that actually creates the illusion of a causal relation e.g. firemen often appear after smoke, not because smoke causes firemen, but because fire causes both smoke and firemen dab Category Hidden variables ... more details
variable is a variable that is accessible in every scope programming scope unless Variable ... considered bad practice precisely because of their non locality a global variable can potentially ... only , and any part of the program may depend on it. ref William Wulf and Mary Shaw, Global Variable ... variable therefore has an unlimited potential for creating mutual dependencies, and adding mutual ... file, such variables effectively have global scope. On the other hand, a variable that is required ..., making the code errno code variable accessible to all modules in a project. Where this global access ... a variable to file scope, and will cause attempts to import it with code extern code to raise ... of a global variable in C programming language C intro comment is wrong? and how about use of the static ... is correct. global does not qualify as a global variable as it is not in scope everywhere . include stdio.h int myGlobal 3 This is the external variable. static void ChangeMyGlobal void myGlobal 5 Reference to external variable in a function. int main void printf d n , myGlobal Reference to external variable in another function. ChangeMyGlobal printf d n , myGlobal return 0 source As the variable ... the value of the variable at any time, understanding the use of the variable may entail understanding ... in other modules. They can lead to problems of naming because 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 and predict. The use of globals make ... , Bash Unix shell bash in Linux , command.exe in DOS and cmd.exe in Windows they are a kind of variable for instance, in unix and related systems an ordinary variable becomes an environment variable ... value of environment variable in one window, that change will not be seen by other window. When a child ... more details
Refimprove date December 2009 An irregular variable is a type of variable star in which variations in brightness show no regular Frequency periodicity . There are two main sub types of irregular variable eruptive and pulsating. Eruptive irregular variables are divided into three categories Group I variables are split into subgroups IA spectral types O to A and IB spectral types F through M . Orion variables , GCVS type IN irregular and nebulous , indigenous to star forming regions, may vary by several magnitudes with rapid changes of up to 1 magnitude in 1 to 10 days, are similarly divided by spectral type into subgroups INA and INB, but with the addition of another subgroup, INT, for T Tauri stars, or INT YY for YY Orionis stars. The third category of eruptive irregulars are the IS stars, which show rapid variations of 0.5 to 1 magnitude in a few hours or days again, these come in subgroups ISA and ISB. Pulsating irregular giants or supergiants, called slow irregular variable s, are all of late spectral types K, M, C, or S , and classed as type L LB for giants and LC for supergiants. How many of these are actually semi regular variables that simply need more study, remains unclear. ref citation title Observing Variable Stars author Gerry Arlen Good year 2003 publisher Springer Science url http books.google.com ?id k9ViYKvKRz0C&pg PA8&lpg PA8&dq 22Irregular variable 22 isbn 9781852334987 ref References Reflist var star stub Category Irregular variables ca Estrella variable irregular de Langsam unregelm ig ver nderlicher Stern es Estrella variable irregular eu Izar aldagarri irregular fr Variable irr guli re ko it Variabile irregolare pl Gwiazda zmienna nieregularna ru sk Nepravideln premenn hviezda tr D zensiz de i en zh ... more details
An Orion variable is a variable star which exhibits irregular variable irregular and eruptive variations in its luminosity and is typically associated with diffuse nebula e. It is thought that these are young stars which will later become regular, non variable stars on the zero age main sequence . Brightness fluctuations can be as much as several magnitudes. T Tauri stars are Orion variables exhibiting characteristic fluorescent violet emission lines from singly ionize d Iron FeII in their stellar classification star spectra , and also emission from Lithium , a metal that usually is destroyed by the nuclear fusion in the stars. FU Orionis stars or simply Fuors , are Orion variables that rise 5 6 magnitudes sink up to one magnitude and stay there for many decades. The prototype is FU Orionis , and other specimens are V1057 Cygni and V1515 Cygni. Of this diverse class of stars, some Orion variables may exhibit a small amplitude up to 1 stellar luminosity magnitude periodic variation, some are characterized by abrupt fadings, and some show spectral characteristics indicating mass downfall upon the star YY Orionis stars . Many of these characteristics may occur in any one Orion variable. References Samus N.N., Durlevich O.V., et al. Combined General Catalog of Variable Stars GCVS4.2, 2004 Ed. External links http www.sai.msu.su groups cluster gcvs gcvs iii vartype.txt GCVS Variability Types Variable star topics Star var star stub Category Irregular variables Category Orion variables ca Variable Ori es Estrella variable Ori n ko it Variabile Orione pt Vari vel rion ru ... more details
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