tgen::permutation

Permutation generator. More...

Inheritance diagram for tgen::permutation:

Classes
struct	value
	Permutation value. More...

Public Member Functions
	permutation (int size)
	Creates permutation generator defined by size.
permutation &	fix (int idx, int val)
	Restricts generator s.t. value at index is fixed.
permutation &	cycles (const std::vector< int > &cycle_sizes)
	Restricts generator s.t. cycle sizes are fixed.
value	gen () const
	Generates a uniformly random value from the set of valid permutations.
Public Member Functions inherited from tgen::gen_base< permutation >
auto	gen_list (int size, Args &&...args) const
	Generates a list of several generation calls.
auto	gen_until (Pred predicate, int max_tries, Args &&...args) const
	Generates a random value from the valid set until a condition is met.
auto	distinct (Args &&...args) const
	Creates distinct generator for current generator.

Detailed Description

Permutation generator.

Defines a set of permutations, subject to restrictions.

A uniformly random tgen::permutation::value from this set of permutations (that satisfies the restrictions) can be generated with tgen::permutation::gen.

Definition at line 2210 of file tgen.h.

Constructor & Destructor Documentation

permutation()

tgen::permutation::permutation ( int size )

inline

Creates permutation generator defined by size.

Parameters

size	Size of the permutation.

Examples

// Permutations of size 10.
auto perm_gen = tgen::permutation(10);

Definition at line 2216 of file tgen.h.

Member Function Documentation

cycles()

permutation & tgen::permutation::cycles ( const std::vector< int > & cycle_sizes )

inline

Restricts generator s.t. cycle sizes are fixed.

Parameters

cycle_sizes

Sizes of cycles.

The sizes of cycles of the generated permutation will be cycle_sizes.

Examples

// Permutations of size 5 with only one cycle.
auto perm_gen = tgen::permutation(5).cycles({5}).gen();

Definition at line 2229 of file tgen.h.

fix()

permutation & tgen::permutation::fix ( int idx, int val )

inline

Restricts generator s.t. value at index is fixed.

Parameters

idx	Index.
val	Value.

Examples

// Permutations of size 10 that start with 1.
auto perm_gen = tgen::permutation(10).fix(0, 1);

Definition at line 2221 of file tgen.h.

gen()

value tgen::permutation::gen ( ) const

inline

Generates a uniformly random value from the set of valid permutations.

Returns

A uniformly random tgen::permutation::value from the set of valid permutations, given the added restrictions.

Exceptions

std::runtime_error

if there is no valid permutation satisfying all added restrictions.

Time complexity

O(n).

Examples

// Generates and prints a random permutation of size 5.
auto val = tgen::permutation(5).gen();
std::cout << val << std::endl;

Definition at line 2385 of file tgen.h.

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The documentation for this struct was generated from the following files:

• /home/runner/work/tgen/tgen/single_include/tgen.h
• permutation.dox