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Instant-use add-on functions for the Wolfram Language

Function Repository Resource:

 MultisetCardinality (1.0.0) current version: 1.0.1 »

Source Notebook

Determine the cardinality for a multiset

Contributed by: Robert B. Nachbar (Wolfram Solutions)

ResourceFunction["MultisetCardinality"][list]

gives the cardinality of the multiset list.

ResourceFunction["MultisetCardinality"][assoc]

gives the cardinality of the Association multiset assoc, effectively giving the total of the values.

Details and Options

The cardinality of a set is the number of elements it contains.
The list need not have the head List.
The values of assoc must be counts—that is, non-negative Integer values.

Examples

Basic Examples (1) 

Give the cardinality:

In[1]:=
ResourceFunction["MultisetCardinality"][{a, b, a, c}]
Out[1]=
In[2]:=
ResourceFunction["MultisetCardinality", ResourceVersion->"1.0.0"][<|"a" -> 2, "b" -> 2, "c" -> 2, "d" -> 0, "e" -> 1|>]
Out[2]=

Scope (1) 

MultisetCardinality works with any head, not just List:

In[3]:=
ResourceFunction["MultisetCardinality"][f[b, b, a]]
Out[3]=

Properties and Relations (2) 

Compare to Length:

In[4]:=
ResourceFunction["MultisetCardinality"][{a, b, a, c}]
Out[4]=
In[5]:=
Length[{a, b, a, c}]
Out[5]=

Compare to Total:

In[6]:=
ResourceFunction["MultisetCardinality", ResourceVersion->"1.0.0"][<|"a" -> 2, "c" -> 2, "d" -> 0|>]
Out[6]=
In[7]:=
Total[<|"a" -> 2, "c" -> 2, "d" -> 0|>]
Out[7]=

Publisher

Robert Nachbar

Requirements

Wolfram Language 11.3 (March 2018) or above

Version History

  • 1.0.1 – 11 August 2023
  • 1.0.0 – 18 February 2019

Related Resources

License Information