Cyclic Permutation - Definition 1

Definition 1

A permutation P over a set S with k elements is called a cyclic permutation with offset t if and only if

the elements of S may be ordered (c < c < ... < c) and the mapping of P may be written as:
p(c ) = c for i = 1, 2, ..., kt, and
p(c) = c for i = kt + 1, kt + 2, ..., k.

Note: Every cyclic permutation of definition type 1 will be constructed with exactly gcd (k, t) disjoint cycles of equal length; see cycles and fixed points.

Cyclic permutations of definition type 1 are also called rotations, or circular shifts.

Example:


\begin{pmatrix} 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 \\ 3 & 4 & 5 & 7 & 6 & 1 & 8 & 2 \end{pmatrix} =
\begin{pmatrix} 1 & 2 & 3 & 4 & 5 & 7 & 6 & 8 \\ 3 & 4 & 5 & 7 & 6 & 8 & 1 & 2 \end{pmatrix} =
(1356)(2478)

is a cyclic permutation with offset 2. It may be constructed with gcd(8, 2) = 2 cycles; see image. The used order is: c := 7, c :=6, c = i else.

Read more about this topic:  Cyclic Permutation

Famous quotes containing the word definition:

    Although there is no universal agreement as to a definition of life, its biological manifestations are generally considered to be organization, metabolism, growth, irritability, adaptation, and reproduction.
    The Columbia Encyclopedia, Fifth Edition, the first sentence of the article on “life” (based on wording in the First Edition, 1935)