order-preserving map
nounUK /ˈɔːdə prɪˌzɜːvɪŋ mæp/
US /ˈɔːrdər prɪˌzɜːrvɪŋ mæp/
A rule that keeps things in the same order when it changes them.
The function that doubles each number is an order-preserving map because smaller numbers stay smaller.
RELATED WORDS
OTHER MEANINGS
2. In mathematics, a function between ordered sets that keeps the order relation intact.
Every increasing function from one ordered set to another is an order-preserving map.
3. A mapping where if one item comes before another, their images also come in that same order.
Sorting by height and then by age uses an order-preserving map on the list.
4. A structure-keeping rule used in computer science to keep sorted data sorted.
The merge step is an order-preserving map that combines two sorted lists.