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Counts[list]

gives an association whose keys are the distinct elements of list, and whose values give the number of times those elements appear in list.

Counts[list,elems]

gives an association whose keys are the distinct elements in elems, and whose values give the number of times those elements appear in list.

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Counts

Counts[list]

gives an association whose keys are the distinct elements of list, and whose values give the number of times those elements appear in list.

Counts[list,elems]

gives an association whose keys are the distinct elements in elems, and whose values give the number of times those elements appear in list.

Details

  • Counts[list] gives an association whose keys are in the same order as they first occur as elements of list. »
  • Counts[list,elems] gives an association whose keys are in the same order as they first occur as elements of elems.

Examples

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Basic Examples  (2)

Count occurrences of unique elements in a list:

Count occurrences of the elements a, b, c and d in a list:

Scope  (1)

Count occurrences in a random list of 0s and 1s:

Repeat, but giving the count of 1s before the count of 0s:

Properties & Relations  (5)

Counts[list] lists elements by the order in which the first appear in list:

Counts[list,elems] lists elements by the order in which the first appear in elems:

Counts[list,elems] will contain totals for all elements in elems, even if they do not appear in list:

CountsBy[list,f] is effectively Counts[Map[f,list]]:

Counts examines literal values:

Count tallies elements matching a pattern:

Wolfram Research (2014), Counts, Wolfram Language function, https://reference.wolfram.com/language/ref/Counts.html (updated 2025).

Text

Wolfram Research (2014), Counts, Wolfram Language function, https://reference.wolfram.com/language/ref/Counts.html (updated 2025).

CMS

Wolfram Language. 2014. "Counts." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2025. https://reference.wolfram.com/language/ref/Counts.html.

APA

Wolfram Language. (2014). Counts. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/Counts.html

BibTeX

@misc{reference.wolfram_2025_counts, author="Wolfram Research", title="{Counts}", year="2025", howpublished="\url{https://reference.wolfram.com/language/ref/Counts.html}", note=[Accessed: 15-August-2025]}

BibLaTeX

@online{reference.wolfram_2025_counts, organization={Wolfram Research}, title={Counts}, year={2025}, url={https://reference.wolfram.com/language/ref/Counts.html}, note=[Accessed: 15-August-2025]}