AIToolbox::SubsetEnumerator< Index > Class Template Reference

This class enumerates all possible vectors of finite subsets over N elements. More...

#include <AIToolbox/Utils/Combinatorics.hpp>

Public Types
using	IdsStorage = std::vector< Index >

Public Member Functions
	SubsetEnumerator (size_t elementsN, Index lowerBound, Index upperBound)
	Default constructor. More...
auto	advance ()
	This function advances the SubsetEnumerator to the next possible subset. More...
bool	isValid () const
	This function returns whether there are more subsets to be enumerated. More...
void	reset ()
	This function resets the enumerator to the valid beginning. More...
auto	subsetsSize () const
	This function returns the number of subsets enumerated over. More...
auto	size () const
	This function returns the size of the range covered. More...
const IdsStorage &	operator* () const
	This operator returns the current combination. More...
const IdsStorage *	operator-> () const
	This operator returns a pointer to the current combination. More...

Detailed Description

template<typename Index>
class AIToolbox::SubsetEnumerator< Index >

This class enumerates all possible vectors of finite subsets over N elements.

Member Typedef Documentation

IdsStorage

template<typename Index >

using AIToolbox::SubsetEnumerator< Index >::IdsStorage = std::vector<Index>

Constructor & Destructor Documentation

SubsetEnumerator()

template<typename Index >

AIToolbox::SubsetEnumerator< Index >::SubsetEnumerator ( size_t  elementsN, Index  lowerBound, Index  upperBound  )

inline

Default constructor.

Parameters

elementsN	The number of elements that the subset should have (<= limit);
lowerBound	Either an integer, or an iterator to the start of a range containing the elements to subset.
upperBound	Either an integer (excluded), or an iterator to the end of a range containing the elements to subset.

Member Function Documentation

advance()

template<typename Index >

auto AIToolbox::SubsetEnumerator< Index >::advance ( )

inline

This function advances the SubsetEnumerator to the next possible subset.

This function iterates first on the last elements of the subset vector, and iterates over the previous ones once it reaches the end. For example, for a subset of length 3 over 6 elements the iteration will look like this:

0, 1, 2 0, 1, 3 0, 1, 4 0, 1, 5 0, 2, 3 0, 2, 4 0, 2, 5 1, 2, 3 etc.

The number returned by this function represents the id of the leftmost (lowest) element that has been changed by the advance. This may be useful in case you need to do some work for the elements that changed in the subset, and want to lose as little time as possible.

Returns

The id of the leftmost element changed by the advance.

isValid()

template<typename Index >

bool AIToolbox::SubsetEnumerator< Index >::isValid ( ) const

inline

This function returns whether there are more subsets to be enumerated.

operator*()

template<typename Index >

const IdsStorage& AIToolbox::SubsetEnumerator< Index >::operator* ( ) const

inline

This operator returns the current combination.

This operator can be called only if isValid() is true. Otherwise behavior is undefined.

Returns

The current combination.

operator->()

template<typename Index >

const IdsStorage* AIToolbox::SubsetEnumerator< Index >::operator-> ( ) const

inline

This operator returns a pointer to the current combination.

This operator can be called only if isValid() is true. Otherwise behavior is undefined.

Returns

The current combination.

reset()

template<typename Index >

void AIToolbox::SubsetEnumerator< Index >::reset ( )

inline

This function resets the enumerator to the valid beginning.

size()

template<typename Index >

auto AIToolbox::SubsetEnumerator< Index >::size ( ) const

inline

This function returns the size of the range covered.

subsetsSize()

template<typename Index >

auto AIToolbox::SubsetEnumerator< Index >::subsetsSize ( ) const

inline

This function returns the number of subsets enumerated over.

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The documentation for this class was generated from the following file:

• include/AIToolbox/Utils/Combinatorics.hpp