NotElement

NotElement[x,dom]

or x∉dom asserts that x is not an element of the domain dom.

NotElement[x1|…|xn,dom]

asserts that none of the x_(i) are elements of dom.

NotElement[patt,dom]

asserts that any expression matching the pattern patt is not an element of the domain dom.

Details

Examples

open allclose all

Basic Examples  (3)

Test whether is not an element of the integers:

Express that is not real:

Enter using !elem:

Scope  (1)

Test domain membership:

Properties & Relations  (1)

For a single variable, the negation of NotElement is automatically converted to Element:

For multiple variables the negation of NotElement is not automatically simplified:

Use LogicalExpand to find the representation in terms of Element:

Wolfram Research (2007), NotElement, Wolfram Language function, https://reference.wolfram.com/language/ref/NotElement.html.

Text

Wolfram Research (2007), NotElement, Wolfram Language function, https://reference.wolfram.com/language/ref/NotElement.html.

CMS

Wolfram Language. 2007. "NotElement." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/NotElement.html.

APA

Wolfram Language. (2007). NotElement. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/NotElement.html

BibTeX

@misc{reference.wolfram_2025_notelement, author="Wolfram Research", title="{NotElement}", year="2007", howpublished="\url{https://reference.wolfram.com/language/ref/NotElement.html}", note=[Accessed: 21-February-2025 ]}

BibLaTeX

@online{reference.wolfram_2025_notelement, organization={Wolfram Research}, title={NotElement}, year={2007}, url={https://reference.wolfram.com/language/ref/NotElement.html}, note=[Accessed: 21-February-2025 ]}