Tally

Tally[list]

tallies the elements in list, listing all distinct elements together with their multiplicities.

Tally[list,test]

uses test to determine whether pairs of elements should be considered equivalent, and gives a list of the first representatives of each equivalence class, together with their multiplicities.

Details

  • Tally[list] lists distinct elements in the order they appear in list.
  • Tally[list] is equivalent to Tally[list,SameQ].

Examples

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Basic Examples  (2)

Obtain tallies for a list of symbols:

Count the elements of a list having the same head:

Scope  (3)

Results are returned in order of first occurrence in the list:

Count the instances of randomly generated integers:

Elements of the list can be any expression:

Applications  (1)

Count occurrences of characters in a string:

Properties & Relations  (5)

Elements with highest frequencies are given by Commonest:

A sorted Tally is equivalent to a list of counts for the Union:

Tally is a discrete analog of BinCounts:

Counts[list] returns an association in which values are the tallies of their keys:

Use the second argument of Tally to construct its corresponding by-function:

Count odd and even numbers in a list:

Introduced in 2007
 (6.0)