lal::generate::_tree_generator< tree_t, > Class Template Reference

Base class for tree generators. More...

#include <tree_generator.hpp>

Public Member Functions
	_tree_generator () noexcept=default
	Default constructor.
	_tree_generator (const uint64_t n) noexcept
	Constructor with number of nodes.
	_tree_generator (const _tree_generator &Gen) noexcept=default
	Default copy constructor.
	_tree_generator (_tree_generator &&Gen) noexcept=default
	Default move constructor.
virtual	~_tree_generator () noexcept=default
	Default destructor.
void	init (const uint64_t n) noexcept
	Initializes the tree generator.
void	clear () noexcept
	Clears the memory used by the generator.
_tree_generator &	operator= (const _tree_generator &Gen)=default
	Default copy assignment operator.
_tree_generator &	operator= (_tree_generator &&Gen)=default
	Default move assignment operator.
tree_t	get_tree () noexcept
	Retrieve the generated tree.
virtual tree_t	yield_tree () noexcept=0
	Yields a tree, advancing the generator if necessary.
void	activate_all_postprocessing_actions () noexcept
	Activates all postprocessing actions.
void	deactivate_all_postprocessing_actions () noexcept
	Deactivates all postprocessing actions.
void	set_normalize_tree (const bool v) noexcept
	Should trees be normalized?
void	set_calculate_size_subtrees (const bool v) noexcept
	Should the size of the subtrees be calculated?
void	set_calculate_tree_type (const bool v) noexcept
	Should the tree be classified into types?

Protected Member Functions
virtual tree_t	__get_tree () noexcept=0
	Retrieve the generated tree.

Protected Attributes
uint64_t	m_n = 0
	Number of vertices.
bool	m_normalize_tree = true
	Normalize the generated tree.
bool	m_calculate_size_subtrees = true
	Calculate the size of the subtrees of the generated rooted tree.
bool	m_calculate_tree_type = true
	Calculate the type of tree of the generated tree.

Static Private Attributes
static constexpr bool	is_free = std::is_base_of_v<graphs::free_tree, tree_t>
	Helpful Boolean value to compact 'if constexpr' expressions.

Detailed Description

template<class tree_t, std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>
class lal::generate::_tree_generator< tree_t, >

Base class for tree generators.

This class is simply a helper for postprocessing a generated tree. The postprocessing actions applied to the tree depends on whether said tree is a rooted tree or a free tree.

The list of methods that govern postprocessing actions are:

• set_normalize_tree (rooted and free trees)
• set_calculate_size_subtrees (rooted trees)
• set_calculate_tree_type (rooted and free trees)

Users can deactivate all postprocessing actions with deactivate_all_postprocessing_actions and activate all of them with activate_all_postprocessing_actions.

There are two types of classes inheriting from this base class. The exhaustive classes, and the random classes. The former provide an exhaustive enumeration of a given type of trees ( \(\{\text{labeled}/\text{unlabeled}\} \times \{\text{rooted}/\text{free}\}\)); the latter generate a given type of tree (the aforementioned four combinations), uniformly at random.

The names of the classes inheriting from this follow one very simple pattern. This is explained in the documentation of the lal::generate namespace (or, if you are a Python user, lal.generate module).

The exhaustive classes have three different usages:

lal::generate::all_2_3_trees Gen(10);
while (not Gen.end()) {
    const auto T = Gen.get_tree();
    // ...
    Gen.next();
}

for (lal::generate::all_2_3_trees Gen(10); not Gen.end(); Gen.next()) {
    const auto T = Gen.get_tree();
    // ...
}

lal::generate::all_2_3_trees Gen(10);
while (not Gen.end()) {
    const auto T = Gen.yield_tree();
    // ...
}

Random classes are a bit simpler to use, with, basically, two different usages:

lal::generate::rand_2_3_trees Gen(10);
for (int i = 0; i < N; ++i) {
    const auto T = Gen.get_tree();
    // ...
}

lal::generate::rand_2_3_trees Gen(10);
for (int i = 0; i < N; ++i) {
    const auto T = Gen.yield_tree();
    // ...
}

Template Parameters

tree_t

Type of tree.

Constructor & Destructor Documentation

_tree_generator() [1/3]

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

lal::generate::_tree_generator< tree_t, >::_tree_generator ( const uint64_t n )

inlinenoexcept

Constructor with number of nodes.

Parameters

n	Number of nodes

_tree_generator() [2/3]

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

lal::generate::_tree_generator< tree_t, >::_tree_generator ( const _tree_generator< tree_t, > & Gen )

defaultnoexcept

Default copy constructor.

Parameters

Gen	Generator of the same type.

_tree_generator() [3/3]

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

lal::generate::_tree_generator< tree_t, >::_tree_generator ( _tree_generator< tree_t, > && Gen )

defaultnoexcept

Default move constructor.

Parameters

Gen	Generator of the same type.

Member Function Documentation

__get_tree()

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

virtual tree_t lal::generate::_tree_generator< tree_t, >::__get_tree ( )

nodiscardprotectedpure virtualnoexcept

Retrieve the generated tree.

See the documentation of each child class to see the correct usage of this method.

Implemented in lal::generate::all_lab_free_trees, lal::generate::all_lab_rooted_trees, lal::generate::all_ulab_free_bistar_trees, lal::generate::all_ulab_free_trees, lal::generate::all_ulab_rooted_trees, lal::generate::rand_lab_free_trees, lal::generate::rand_lab_rooted_trees, lal::generate::rand_ulab_free_trees, and lal::generate::rand_ulab_rooted_trees.

activate_all_postprocessing_actions()

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

void lal::generate::_tree_generator< tree_t, >::activate_all_postprocessing_actions ( )

inlinenoexcept

Activates all postprocessing actions.

The full list of postprocessing actions can be found in the documentation of this class.

deactivate_all_postprocessing_actions()

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

void lal::generate::_tree_generator< tree_t, >::deactivate_all_postprocessing_actions ( )

inlinenoexcept

Deactivates all postprocessing actions.

The full list of postprocessing actions can be found in the documentation of this class.

get_tree()

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

tree_t lal::generate::_tree_generator< tree_t, >::get_tree ( )

inlinenodiscardnoexcept

Retrieve the generated tree.

This function first calls __get_tree and then modifies the generated tree according to the values:

• set_normalize_tree
• set_calculate_size_subtrees
• set_calculate_tree_type

Returns

A free/rooted tree depending on the type of the class inheriting from this. The type of generation of tree differs from one type of class to another.

operator=() [1/2]

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

_tree_generator & lal::generate::_tree_generator< tree_t, >::operator= ( _tree_generator< tree_t, > && Gen )

default

Default move assignment operator.

Parameters

Gen	Generator of the same type.

operator=() [2/2]

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

_tree_generator & lal::generate::_tree_generator< tree_t, >::operator= ( const _tree_generator< tree_t, > & Gen )

default

Default copy assignment operator.

Parameters

Gen	Generator of the same type.

set_calculate_size_subtrees()

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

void lal::generate::_tree_generator< tree_t, >::set_calculate_size_subtrees ( const bool v )

inlinenoexcept

Should the size of the subtrees be calculated?

Parameters

v	Boolean value.

set_calculate_tree_type()

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

void lal::generate::_tree_generator< tree_t, >::set_calculate_tree_type ( const bool v )

inlinenoexcept

Should the tree be classified into types?

See lal::graphs::tree_type for details on the classification.

Parameters

v	Boolean value.

set_normalize_tree()

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

void lal::generate::_tree_generator< tree_t, >::set_normalize_tree ( const bool v )

inlinenoexcept

Should trees be normalized?

Parameters

v	Boolean value.

yield_tree()

template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>

virtual tree_t lal::generate::_tree_generator< tree_t, >::yield_tree ( )

nodiscardpure virtualnoexcept

Yields a tree, advancing the generator if necessary.

In case the class that inherits from this one is exhaustive then this function also moves the generator forward with its appropriate method. If the class is random, then it just calls get_tree().

Returns

A free/rooted tree depending on the type of the class inheriting from this. The type of generation of tree differs from one type of class to another.

Postcondition

The generator advances to the next tree.

Implemented in lal::generate::all_lab_free_trees, lal::generate::all_lab_rooted_trees, lal::generate::all_ulab_free_bistar_trees, lal::generate::all_ulab_free_trees, lal::generate::all_ulab_rooted_trees, lal::generate::rand_lab_free_trees, lal::generate::rand_lab_rooted_trees, lal::generate::rand_ulab_free_trees, and lal::generate::rand_ulab_rooted_trees.

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

• lal/generate/tree_generator.hpp