cpp_unordered_multimap: Create unordered multimap

In cppcontainers: 'C++' Standard Template Library Containers

Create unordered multimap

Description

Create an unordered multimap. Unordered multimaps are key-value pairs with non-unique keys.

Usage

cpp_unordered_multimap(keys, values)

Arguments

keys	An integer, numeric, character, or logical vector.
values	An integer, numeric, character, or logical vector.

Details

Unordered multimaps are associative containers. They do not provide random access through an index. I.e. m[2] does not return the second element.

Unordered means that the container does not enforce elements to be stored in a particular order. This makes unordered multimaps in some applications faster than multimaps.

C++ unordered_multimap methods implemented in this package are bucket_count, clear, contains, count, emplace, empty, erase, insert, load_factor, max_bucket_count, max_load_factor, max_size, merge, rehash, reserve, and size. The package also adds the == operator and various helper functions (print, to_r, type).

All object-creating methods in this package begin with cpp_ to avoid clashes with functions from other packages, such as utils::stack and base::vector.

Value

Returns a CppUnorderedMultimap object referencing an unordered_multimap in C++.

See Also

cpp_map, cpp_unordered_map, cpp_multimap.

Examples

m <- cpp_unordered_multimap(c("world", "hello", "there", "hello"), 4:7)
m
# ["there",6] ["hello",5] ["hello",7] ["world",4]

print(m, n = 2)
# 

erase(m, "hello")
m
# ["there",6] ["world",4]

contains(m, "there")
# [1] TRUE

cppcontainers documentation built on Sept. 9, 2025, 5:55 p.m.