WOLFRAM

Wolfram Language & System Documentation Center

MapAll[f,expr]

or f//@expr applies f to every subexpression in expr.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Options  
Heads  
Applications  
Properties & Relations  
See Also
Tech Notes
Related Guides
History
Cite this Page

MapAll

MapAll[f,expr]

or f//@expr applies f to every subexpression in expr.

Details and Options

  • MapAll[f,expr] is equivalent to Map[f,expr,{0,Infinity}].
  • MapAll[f,expr,Heads->True] applies f to heads in expr, and their parts.
  • If expr is an Association object, MapAll[f,expr] applies f only to the values in the association. »
  • If expr is a SparseArray object or structured array, MapAll[f,expr] applies f to the values or subarrays just as it would on the corresponding ordinary list. »

Examples

open all close all

Basic Examples  (2)

Apply f to every subpart of an expression:

Alternative input form:

Apply h to every value in associations:

Scope  (4)

MapAll can be used on expressions with any head:

The function can be mapped onto the heads as well:

MapAll can be used on sparse arrays:

Use MapAll with structured arrays, such as SymmetrizedArray:

Options  (1)

Heads  (1)

Apply f to heads as well as ordinary parts of expressions:

Applications  (1)

Show nesting structure of an expression:

Properties & Relations  (2)

MapAll is equivalent to a specific level specification in Map:

MapAll maps also around the whole expression; Map[f,expr,∞] does not:

Wolfram Research (1988), MapAll, Wolfram Language function, https://reference.wolfram.com/language/ref/MapAll.html.

Text

Wolfram Research (1988), MapAll, Wolfram Language function, https://reference.wolfram.com/language/ref/MapAll.html.

CMS

Wolfram Language. 1988. "MapAll." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/MapAll.html.

APA

Wolfram Language. (1988). MapAll. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/MapAll.html

BibTeX

@misc{reference.wolfram_2025_mapall, author="Wolfram Research", title="{MapAll}", year="1988", howpublished="\url{https://reference.wolfram.com/language/ref/MapAll.html}", note=[Accessed: 12-August-2025]}

BibLaTeX

@online{reference.wolfram_2025_mapall, organization={Wolfram Research}, title={MapAll}, year={1988}, url={https://reference.wolfram.com/language/ref/MapAll.html}, note=[Accessed: 12-August-2025]}