Undefined may refer to:
Mathematics
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Undefined (mathematics)
In mathematics, the term undefined refers to a value, function, or other expression that cannot be assigned a meaning within a specific formal system.
Attempting to assign or use an undefined value within a particular formal system, may pr ...
, with several related meanings
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Indeterminate form
Indeterminate form is a mathematical expression that can obtain any value depending on circumstances. In calculus, it is usually possible to compute the limit of the sum, difference, product, quotient or power of two functions by taking the corres ...
, in calculus
Computing
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Undefined behavior
In computer programming, a program exhibits undefined behavior (UB) when it contains, or is executing code for which its programming language specification does not mandate any specific requirements. This is different from unspecified behavior, ...
, computer code whose behavior is not specified under certain conditions
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Undefined value
In computing (particularly, in programming), undefined value is a condition where an expression does not have a correct value, although it is syntactically correct. An undefined value must not be confused with empty string, Boolean "false" ...
, a condition where an expression does not have a correct value
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Undefined variable An undefined variable in the source code of a computer program is a variable that is accessed in the code but has not been declared by that code."undefined variable." YourDictionary, n.d. Web. 24 July 2013. .
In some programming languages, an imp ...
*Undefined, a function or variable lacking a
declaration
*Undefined, a variable lacking
initialization
*Undefined, an unavailable
linker
Linker or linkers may refer to:
Computing
* Linker (computing), a computer program that takes one or more object files generated by a compiler or generated by an assembler and links them with libraries, generating an executable program or shar ...
symbol (function, or global variable)
Other uses
*Undefined, something that lacks any
definition
A definition is a statement of the meaning of a term (a word, phrase, or other set of symbols). Definitions can be classified into two large categories: intensional definitions (which try to give the sense of a term), and extensional definitio ...
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Undefined citizenship
Estonian citizenship law details the conditions by which a person is a citizen of Estonia. The primary law currently governing these requirements is the Citizenship Act, which came into force on 1 April 1995.
Estonia is a member state of the ...
, a post-Soviet form of statelessness in Estonia
See also
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Null (disambiguation)
Null may refer to:
Science, technology, and mathematics Astronomy
*Nuller, an optical tool using interferometry to block certain sources of light Computing
*Null (SQL) (or NULL), a special marker and keyword in SQL indicating that a data value do ...
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Void (disambiguation)
Void may refer to:
Science, engineering, and technology
* Void (astronomy), the spaces between galaxy filaments that contain no galaxies
* Void (composites), a pore that remains unoccupied in a composite material
* Void, synonym for vacuum, a s ...
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Invalid (disambiguation)
Invalid may refer to:
* Patient, a sick person
* one who is confined to home or bed because of illness, disability or injury (sometimes considered a politically incorrect term)
* Invalid (film), a 2023 Slovak black comedy movie
* .invalid, a top-l ...
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Definition (disambiguation)
A definition is a statement of the meaning of a term.
Definition may also refer to:
Science, mathematics and computing
* In computer programming languages, a declaration that reserves memory for a variable or gives the body of a subroutine
* D ...
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Definable (disambiguation)
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