DeleteMissing
✖
DeleteMissing
applies DeleteMissing to any lists or associations that occur within the first n levels of expr.
considers an element at level n to be missing if Missing occurs within the first d levels of the element.
Details
- DeleteMissing[{lhs1->rhs1,…}] deletes any elements of the list when rhsi has head Missing.
- DeleteMissing[expr,Infinity] specifies that DeleteMissing should search to arbitrary depth for expressions with head Missing and delete them.
- DeleteMissing[expr,1,Infinity] indicates that elements at the first level should be removed if they contain Missing at any depth.
- When searching multiple levels, DeleteMissing will only search within lists and associations and ignores expressions with other heads.
- DeleteMissing[Missing[]] returns Sequence[].
Examples
open allclose allBasic Examples (2)Summary of the most common use cases
Scope (3)Survey of the scope of standard use cases
Delete elements with head Missing up to level 2:
https://wolfram.com/xid/0dqvzugjz6a-kxzgmo
Delete missing elements at all levels:
https://wolfram.com/xid/0dqvzugjz6a-bs0b1q
Delete elements at level 1 if they contain an element with head Missing:
https://wolfram.com/xid/0dqvzugjz6a-71tcyi
Delete elements at level 1 if they contain a missing expression anywhere inside:
https://wolfram.com/xid/0dqvzugjz6a-ldrgym
DeleteMissing deletes complete rules when the right-hand side is Missing:
https://wolfram.com/xid/0dqvzugjz6a-ku2x8c
Properties & Relations (2)Properties of the function, and connections to other functions
DeleteMissing[expr] deletes missing elements at the top level only:
https://wolfram.com/xid/0dqvzugjz6a-d9o6qb
DeleteMissing[list] is effectively equivalent to DeleteCases[list,_Missing]:
https://wolfram.com/xid/0dqvzugjz6a-i1bcqt
https://wolfram.com/xid/0dqvzugjz6a-i6dpgw
Possible Issues (1)Common pitfalls and unexpected behavior
DeleteMissing does not enter heads other than List or Association:
https://wolfram.com/xid/0dqvzugjz6a-wwbyic
https://wolfram.com/xid/0dqvzugjz6a-q5gqkc
Wolfram Research (2014), DeleteMissing, Wolfram Language function, https://reference.wolfram.com/language/ref/DeleteMissing.html (updated 2015).
Text
Wolfram Research (2014), DeleteMissing, Wolfram Language function, https://reference.wolfram.com/language/ref/DeleteMissing.html (updated 2015).
Wolfram Research (2014), DeleteMissing, Wolfram Language function, https://reference.wolfram.com/language/ref/DeleteMissing.html (updated 2015).
CMS
Wolfram Language. 2014. "DeleteMissing." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2015. https://reference.wolfram.com/language/ref/DeleteMissing.html.
Wolfram Language. 2014. "DeleteMissing." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2015. https://reference.wolfram.com/language/ref/DeleteMissing.html.
APA
Wolfram Language. (2014). DeleteMissing. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/DeleteMissing.html
Wolfram Language. (2014). DeleteMissing. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/DeleteMissing.html
BibTeX
@misc{reference.wolfram_2024_deletemissing, author="Wolfram Research", title="{DeleteMissing}", year="2015", howpublished="\url{https://reference.wolfram.com/language/ref/DeleteMissing.html}", note=[Accessed: 07-January-2025
]}
BibLaTeX
@online{reference.wolfram_2024_deletemissing, organization={Wolfram Research}, title={DeleteMissing}, year={2015}, url={https://reference.wolfram.com/language/ref/DeleteMissing.html}, note=[Accessed: 07-January-2025
]}