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9 Permutations
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This chapter describes functions for creating and manipulating
permutations.  A permutation p is represented by an array of n integers
in the range 0 to n-1, where each value p_i occurs once and only once.
The application of a permutation p to a vector v yields a new vector v'
where v'_i = v_{p_i}.  For example, the array (0,1,3,2) represents a
permutation which exchanges the last two elements of a four element
vector.  The corresponding identity permutation is (0,1,2,3).

Note that the permutations produced by the linear algebra routines
correspond to the exchange of matrix columns, and so should be
considered as applying to row-vectors in the form v' = v P rather than
column-vectors, when permuting the elements of a vector.

The functions described in this chapter are defined in the header file
‘gsl_permutation.h’.

The Permutation struct

Permutation allocation

Accessing permutation elements

Permutation properties

Permutation functions

Applying Permutations

Reading and writing permutations

Permutations in cyclic form

Examples

Examples<4>.

References and Further Reading

References and Further Reading<5>.