Definitions
from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun A function that is onto.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun mathematics A
function of "many-to-one" mapping relationship; more formally, f: X → Y is a surjection if and only if, for every y in thecodomain Y, there is at least one x in thedomain X with f(x) = y.
Etymologies
from The American Heritage® Dictionary of the English Language, 4th Edition
from Wiktionary, Creative Commons Attribution/Share-Alike License
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Examples
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'' 'surjection' '' is a [[function (mathematics) | function]] for which every possible output value occurs for one or more input values: that is, its image is the whole of its codomain.
Citizendium, the Citizens' Compendium - Recent changes [en] 2008
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'' 'surjection' '' is a [[function (mathematics) | function]] for which every possible output value occurs for one or more input values: that is, its image is the whole of its codomain.
Citizendium, the Citizens' Compendium - Recent changes [en] 2008
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It is easy to check that this function satisfies the relation, which has to be a surjection since the sequence is strictly increasing..
Gowers's Weblog 2010
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But the Zariski topology is not metrizable … is a surjection of sheaves (exercise!), yet the map on global sections is not surjective.
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If you think about it, Arrays and Maps share the same underlying formalism (a surjection, not to put too fine a point on it), and in some languages, notably PHP, there isn't a user-visible difference between them.
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If you think about it, Arrays and Maps share the same underlying formalism (a surjection, not to put too fine a point on it), and in some languages, notably PHP, there isn't a user-visible difference between them.
Stevey's Blog Rants Steve Yegge 2008
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If you think about it, Arrays and Maps share the same underlying formalism (a surjection, not to put too fine a point on it), and in some languages, notably PHP, there isn't a user-visible difference between them.
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