Is there a name for functions that are their own inverses

Question

There are terms for various kinds of functions (or operators) such as...

associative - (a # b) # c  =  a # (b # c)
commutative - a # b  =  b # a
idempotent  - f (f (x)) = f (x)

Is there a similar name for functions that are their own inverse?

f (f (x)) = x

score 13 · Accepted Answer · answered Sep 27 '13 at 17:03

13

It is called as an involution.

answered Sep 27 '13 at 17:03

JiminP

Thanks - have to wait a few minutes before I can accept, but this is the answer. – Sep 27 '13 at 17:05
1

Some examples of involutions are shown here – Mufasa Sep 27 '13 at 17:08
The most trivial involution is f(x) = x. – Tortoise Sep 27 '13 at 23:00

score 6 · Answer 2 · answered Sep 27 '13 at 17:04

6

Such a function is called an involution.

answered Sep 27 '13 at 17:04

Guest

2 Answers2