Here is a list of all documented namespace functions with links to the namespaces they belong to:

### - i -

- identity_element() : __gnu_cxx
- includes() : std
- inclusive_scan() : std
- inner_product() : std
- inout_ptr() : std
- inplace_merge() : std
- inserter() : std
- internal() : std
- iota() : __gnu_cxx, std
- is_am() : std::chrono
- is_corresponding_member() : std
- is_heap() : std
- is_heap_until() : std
- is_partitioned() : std
- is_permutation() : std
- is_pm() : std::chrono
- is_pointer_interconvertible_with_class() : std
- is_sorted() : std
- is_sorted_until() : std
- is_sufficiently_aligned() : std
- isalnum() : std
- isalpha() : std
- isblank() : std
- iscntrl() : std
- isdigit() : std
- isgraph() : std
- islower() : std
- isprint() : std
- ispunct() : std
- isspace() : std
- isupper() : std
- isxdigit() : std
- iter_swap() : std