WOLFRAM

Wolfram Language & System Documentation Center

Commonest[list]

gives a list of the elements that are the most common in list.

Commonest[list,n]

gives a list of the n most common elements in list.

Details
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Applications  
Properties & Relations  
Possible Issues  
See Also
Related Guides
Related Workflows
History
Cite this Page

Commonest

Commonest[list]

gives a list of the elements that are the most common in list.

Commonest[list,n]

gives a list of the n most common elements in list.

Details

  • When several elements occur with equal frequency, Commonest[list,…] picks first the ones that occur first in list.
  • Commonest[list,n] returns the n commonest elements in the order they appear in list.
  • Commonest[list,UpTo[n]] returns the n commonest elements, or as many as are available.

Examples

open all close all

Basic Examples  (3)

Obtain the elements with the highest frequency:

Wolfram Language code: Commonest[{b, a, c, 2, a, b, 1, 2}]

Obtain the 4 most common elements:

Wolfram Language code: Commonest[{b, a, c, 2, a, b, 1, 2}, 4]

Obtain the 6 most common elements, or as many as there are if fewer:

Wolfram Language code: Commonest[{b, a, c, 2, a, b, 1, 2}, UpTo[6]]

Scope  (4)

Exact input yields exact output:

Wolfram Language code: Commonest[{1, 2, 2, 3, 3, 3, 4}]
Wolfram Language code: Commonest[{a, E, Sin[y], E, a, 7}]

Approximate input yields approximate output:

Wolfram Language code: Commonest[N[{1, 2, 2, 3, 3, 3, 4}]]
Wolfram Language code: Commonest[N[{1, 2, 2, 3, 3, 3, 4}, 30]]

Works with large arrays:

Wolfram Language code: Commonest[Join[Table[1, {10 ^ 7}], Table[3, {10 ^ 4}], {7, 8}]]
Wolfram Language code: Commonest[Join[Table[1, {10 ^ 7}], Table[3, {10 ^ 4}], {7, 8}], 2]

Works with data involving quantities:

Wolfram Language code: data = Quantity[{1, 2, 2, 3, 3, 3, 4}, "Meters"]
Wolfram Language code: Commonest[data]

Applications  (2)

Find the mode of a set of random integers:

Wolfram Language code: Commonest[RandomInteger[20, 1000]]

Find the most frequently occurring elements in the columns of a matrix:

Wolfram Language code: Map[Commonest, Transpose[RandomInteger[20, {1000, 5}]]]

Find the mode for the heights of the children in a class:

Wolfram Language code: heights = Quantity[{134, 143, 131, 140, 145, 136, 131, 136, 143, 136, 133, 145, 147, 150, 150, 146, 137, 143, 132, 142, 145, 136, 144, 135, 141}, "Centimeters"];
Wolfram Language code: ListPlot[heights, Filling -> Axis, AxesLabel -> Automatic]
Wolfram Language code: Commonest[heights]
Wolfram Language code: mode = %[[1]]
Wolfram Language code: ListPlot[{heights, {{0, mode}, {Length[heights], mode}}}, Joined -> {False, True}, Filling -> {1 -> 0}, AxesLabel -> Automatic]

Properties & Relations  (1)

Commonest gives elements with the largest Tally values:

Wolfram Language code: data = RandomInteger[10, 50];
Wolfram Language code: Commonest[data]
Wolfram Language code: tallies = Tally[data]
Wolfram Language code: Select[tallies, #[[2]] === Max[tallies[[All, 2]]]&]

Possible Issues  (1)

A message is generated if there are fewer distinct elements than requested:

Wolfram Language code: Commonest[{a, E, Sin[y], E, a, 1.5, N[3, 20]}, 10]
Wolfram Research (2007), Commonest, Wolfram Language function, https://reference.wolfram.com/language/ref/Commonest.html (updated 2015).

Text

Wolfram Research (2007), Commonest, Wolfram Language function, https://reference.wolfram.com/language/ref/Commonest.html (updated 2015).

CMS

Wolfram Language. 2007. "Commonest." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2015. https://reference.wolfram.com/language/ref/Commonest.html.

APA

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

BibTeX

@misc{reference.wolfram_2026_commonest, author="Wolfram Research", title="{Commonest}", year="2015", howpublished="\url{https://reference.wolfram.com/language/ref/Commonest.html}", note=[Accessed: 12-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_commonest, organization={Wolfram Research}, title={Commonest}, year={2015}, url={https://reference.wolfram.com/language/ref/Commonest.html}, note=[Accessed: 12-June-2026]}