Unique

Unique(a, i)

Returns a maximal subset of index «i» such that each indicated slice of array «a» along «i» is unique.

Unique can be used to remove duplicate slices from an array, or to identify a single member of each equivalence class.

Example

Let:

DataSet →

	Field ▶
PersonNum ▼	LastName	FirstName	Company
1	Smith	Bob	Acme
2	Jones	John	Acme
3	Johnson	Bob	Floorworks
4	Smith	Bob	Acme

Then:

Unique(DataSet, PersonNum) → [1, 2, 3]

Unique(DataSet[Field = 'Company'], PersonNum) → [1, 3]

Optional parameters

Position

By default, Unique returns the elements of the index. Setting the optional parameter «position» equal true (position: true) will return the positions of the elements in «i» , rather than the elements themselves (see Associative vs. Positional Indexing).

CaseInsensitive

When applying Unique to text values, values are considered by default in a case-sensitive fashion, for example, "Apple" and "apple" are considered distinct elements.

Specifying caseInsensitive: true ignores differences in upper and lower case in text values when determining if values are unique.