functions

Function may refer to:Function (biology), explaining why a feature was created Function (mathematics), an abstract entity that associates an input to a corresponding output according to some ruleFunction (engineering), related to the utility/goal of a propertyFunction (computer science), or subroutine, a portion of code within a larger program, performs a specific taskFunction object, or functor or functionoid, a concept of object-oriented programmingGrammatical function, in language studies, the purpose of a word or phrase in a sentenceA formal event such as a party or meetingFunctional group in organic chemistry (for example, "This compound has two carbonyl functions")
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1. <mathematics C" is a subset of D x C such that:
1. For each d in D there exists some c in C such that (d,c) is an element of f. I.e. the function is defined for every element of D.
2. For each d in D, c1 and c2 in C, if both (d,c1) and (d,c2) are elements of f then c1 = c2. I.e. the function is uniquely defined for every element of D.
See also image, inverse, partial function.
2. Computing usage derives from the mathematical term but is much less strict. In programming (except in functional programming), a function may return different values each time it is called with the same argument values and may have side effects.
A procedure is a function which returns no value but has only side-effects. The C language, for example, has no procedures, only functions. ANSI C even defines a type, void, for the result of a function that has no result.
(1996-09-01)

Noun
1. a mathematical relation such that each element of one set is associated with at least one element of another set
(synonym) mathematical function
(hypernym) mathematical relation
(hyponym) inverse function
(classification) mathematics, math, maths
2. what something is used for; "the function of an auger is to bore holes"; "ballet is beautiful but what use is it?"
(synonym) purpose, role, use
(hypernym) utility, usefulness
(hyponym) raison d'etre
(attribute) functional
(derivation) serve
3. the actions and activities assigned to or required or expected of a person or group; "the function of a teacher"; "the government must do its part"; "play its role"
(synonym) office, part, role
(hypernym) duty
(hyponym) capacity
(derivation) officiate
4. a relation such that one thing is dependent on another; "height is a function of age"; "price is a function of supply and demand"
(hypernym) relation
5. a formal or official social gathering or ceremony; "it was a black-tie function"
(hypernym) social gathering, social affair
6. a vaguely specified social event; "the party was quite an affair"; "an occasion arranged to honor the president"; "a seemingly endless round of social functions"
(synonym) affair, occasion, social occasion, social function
(hypernym) social event
(hyponym) party
7. a set sequence of steps, part of larger computer program
(synonym) routine, subroutine, subprogram, procedure
(hypernym) software, software system, software package, package
(hyponym) cataloged procedure
(part-holonym) program, programme, computer program, computer programme
Verb
1. perform as expected when applied; "The washing machine won't go unless it's plugged in"; "Does this old car still run well?"; "This old radio doesn't work anymore"
(synonym) work, operate, go, run
(antonym) malfunction, misfunction
(hyponym) double
(verb-group) run
(derivation) operation, functioning, performance
2. serve a purpose, role, or function; "The tree stump serves as a table"; "The female students served as a control group"; "This table would serve very well"; "His freedom served him well"; "The table functions as a desk"
(synonym) serve
(hypernym) suffice, do, answer, serve
(hyponym) prelude
(verb-group) service, serve
(derivation) purpose, role, use
3. perform duties attached to a particular office or place or function; "His wife officiated as his private secretary"
(synonym) officiate
(hypernym) serve
(derivation) office, part, role