lal::io Namespace Reference

Input/Output functions and processing of treebanks. More...

Classes
class	_treebank_processor_base
	The processor base class. More...
class	head_vector_error
	Head vector error report class. More...
class	treebank_collection_processor
	Automatic processing of treebank collections. More...
class	treebank_collection_reader
	A reader for a collection of treebanks. More...
class	treebank_collection_report
	Report on a treebank collection. More...
struct	treebank_collection_report_location
	An auxiliary struct in replacement of std::tuple. More...
class	treebank_file_error
	Treebank file error report class. More...
class	treebank_file_report
	Report on a treebank file. More...
class	treebank_processor
	Automatic processing of treebank files. More...
class	treebank_reader
	A reader for a single treebank file. More...

Enumerations
enum class	head_vector_error_type {   invalid_integer , head_out_bounds , wrong_number_of_roots , wrong_number_of_edges ,   graph_has_cycles , isolated_vertex , self_loop }
	The different types of errors that can be present in a head vector. More...
enum class	treebank_feature_type {   num_nodes , second_moment_degree , second_moment_degree_out , third_moment_degree ,   third_moment_degree_out , sum_squared_degrees , sum_squared_out_degrees , sum_cubed_degrees ,   sum_cubed_out_degrees , num_pairs_independent_edges , head_initial , hubiness ,   sum_hierarchical_distances , mean_hierarchical_distance , tree_centre , tree_centroid ,   tree_diameter , tree_caterpillar_distance , num_crossings , predicted_num_crossings ,   exp_num_crossings , var_num_crossings , z_score_num_crossings , sum_edge_lengths ,   exp_sum_edge_lengths , exp_sum_edge_lengths_bipartite , exp_sum_edge_lengths_projective , exp_sum_edge_lengths_planar ,   var_sum_edge_lengths , z_score_sum_edge_lengths , min_sum_edge_lengths , min_sum_edge_lengths_bipartite ,   min_sum_edge_lengths_planar , min_sum_edge_lengths_projective , max_sum_edge_lengths , max_sum_edge_lengths_1_thistle ,   max_sum_edge_lengths_bipartite , max_sum_edge_lengths_planar , max_sum_edge_lengths_projective , mean_dependency_distance ,   flux_max_weight , flux_mean_weight , flux_min_weight , flux_max_left_span ,   flux_mean_left_span , flux_min_left_span , flux_max_right_span , flux_mean_right_span ,   flux_min_right_span , flux_max_size , flux_mean_size , flux_min_size ,   flux_max_RL_ratio , flux_mean_RL_ratio , flux_min_RL_ratio , flux_max_WS_ratio ,   flux_mean_WS_ratio , flux_min_WS_ratio , tree_type , syntactic_dependency_tree_class ,   __last_value }
	The features that can be computed in automatic processing of treebanks. More...
enum class	treebank_file_error_type {   no_error , no_features , treebank_file_does_not_exist , treebank_file_could_not_be_opened ,   output_file_could_not_be_opened , malformed_treebank_file , main_file_does_not_exist , main_file_could_not_be_opened ,   output_directory_could_not_be_created , output_join_file_could_not_be_opened , treebank_result_file_could_not_be_opened , some_treebank_file_failed ,   malformed_treebank_collection }
	Possible errors that can arise while processing a collection. More...

Functions
std::vector< head_vector_error >	check_correctness_head_vector (const head_vector &head_vector) noexcept
	Checks the correctness of a head vector.
std::vector< head_vector_error >	check_correctness_head_vector (const std::string &head_vector_str) noexcept
	Checks the correctness of a head vector.
treebank_file_report	check_correctness_treebank (const std::string &treebank_filename) noexcept
	Checks the correctness of a treebank collection.
treebank_collection_report	check_correctness_treebank_collection (const std::string &main_file_name, const std::size_t n_threads=1) noexcept
	Checks the correctness of a treebank collection.
std::optional< graphs::undirected_graph >	read_edge_list_undirected_graph (const std::string &filename, const bool norm=true, const bool check_norm=true) noexcept
	Reads a undirected graph in edge list format.
std::optional< graphs::directed_graph >	read_edge_list_directed_graph (const std::string &filename, const bool norm=true, const bool check_norm=true) noexcept
	Reads a directed graph in edge list format.
std::optional< graphs::free_tree >	read_edge_list_free_tree (const std::string &filename, const bool norm=true, const bool check_norm=true) noexcept
	Reads a free tree in edge list format.
std::optional< graphs::rooted_tree >	read_edge_list_rooted_tree (const std::string &filename, const bool norm=true, const bool check_norm=true) noexcept
	Reads a rooted tree in edge list format.
template<class graph_t , std::enable_if_t< std::is_base_of_v< graphs::graph, graph_t >, bool > = true>
std::optional< graph_t >	read_edge_list (const std::string &filename, const bool norm=true, const bool check_norm=true) noexcept
	Reads a graph in edge list format.
std::optional< graphs::free_tree >	read_head_vector_free_tree (const std::string &filename, const bool norm=true, const bool check_norm=true) noexcept
	Reads a free tree in head vector format.
std::optional< graphs::rooted_tree >	read_head_vector_rooted_tree (const std::string &filename, const bool norm=true, const bool check_norm=true) noexcept
	Reads a rooted tree in head vector format.
template<class tree_t , std::enable_if_t< std::is_base_of_v< graphs::tree, tree_t >, bool > = true>
std::optional< tree_t >	read_head_vector (const std::string &filename, const bool norm=true, const bool check_norm=true) noexcept
	Reads a rooted tree in head vector format.
treebank_file_error	process_treebank_collection (const std::string &treebank_collection_main_file, const std::string &output_directory, const std::size_t num_threads=1) noexcept
	Automatically process a treebank collection.
constexpr std::string_view	treebank_feature_string (const io::treebank_feature_type &tf) noexcept
	Converts a lal::io::treebank_feature_type value into a string.
constexpr std::size_t	treebank_feature_to_index (const io::treebank_feature_type &tf) noexcept
	Returns the index of the input treebank feature.
constexpr io::treebank_feature_type	index_to_treebank_feature (const std::size_t idx) noexcept
	Returns the treebank feature corresponding to the input index.
constexpr std::string_view	treebank_feature_index_to_string (const std::size_t idx) noexcept
	Returns the treebank feature corresponding to the index as a string.
treebank_file_error	process_treebank (const std::string &treebank_file, const std::string &output_file) noexcept
	Automatically process a treebank.

Variables
constexpr std::size_t	__treebank_feature_size
	The total number of features available.

Detailed Description

Input/Output functions and processing of treebanks.

This namespace contains the functions for input/output operations.

The most basic operations read a graph from a file. The formats supported for reading are:

• Edge list (see Edge list page page for details). See lal::io::read_edge_list functions.
• Head vector (see Head vector page for details). See lal::io::read_head_vector functions.

Users can also process collection of trees (called treebank files), and collections of treebank files (obviously, a treebank collection). One can process automatically a treebank file (see lal::io::treebank_processor) or a treebank collection (see lal::io::treebank_collection_processor), and iterate through the trees of a treebank file (see lal::io::treebank_reader) and through the treebank files within a treebank collection (see lal::io::treebank_collection_reader).

A treebank file is a file containing only head vectors of trees. Such head vectors may not be formatted correctly (from the standpoint of this library), and so users of the library are also provided with function to check the correctess of such files (see lal::io::check_correctness_treebank and lal::io::check_correctness_treebank_collection). Users are encouraged to read the documentation of these classes to know more about treebank files and collection of treebanks and how to process them with the library.

Enumeration Type Documentation

head_vector_error_type

enum class lal::io::head_vector_error_type

strong

The different types of errors that can be present in a head vector.

Enumerator
invalid_integer	The current head index is not a valid non-integer integer number. It could be a letter, a negative number, ...
head_out_bounds	The current head index is a valid non-negative integer value, but points outside the head vector.
wrong_number_of_roots	The head vector contains too many roots.
wrong_number_of_edges	The graph does not contain enough edges to be a tree.
graph_has_cycles	The graph contains an undirected cycle, that is, the graph is not a tree.
isolated_vertex	There are isolated vertices in the graph.
self_loop	The current head index points to itself.

treebank_feature_type

enum class lal::io::treebank_feature_type

strong

The features that can be computed in automatic processing of treebanks.

Classes lal::io::treebank_collection_processor and lal::io::treebank_processor are designed to process treebanks in an automatic fashion, meaning that they process the trees and calculate a fixed set of features, the results of which are stored in files. In this enumeration users will find a complete list of all the features that can be calculated using those two classes.

Enumerator
num_nodes	Number of nodes of the tree.
second_moment_degree	Second moment of degree \(\langle k^2 \rangle\). See lal::properties::moment_degree for details.
second_moment_degree_out	Second moment of out-degree \(\langle k_{out}^2 \rangle\). See lal::properties::moment_out_degree for details.
third_moment_degree	Third moment of degree \(\langle k^3 \rangle\). See lal::properties::moment_degree for details.
third_moment_degree_out	Third moment of out-degree \(\langle k_{out}^3 \rangle\). See lal::properties::moment_out_degree for details.
sum_squared_degrees	Sum of squared degrees. See lal::properties::sum_powers_degrees for details.
sum_squared_out_degrees	Sum of squared out-degrees. See lal::properties::sum_powers_out_degrees for details.
sum_cubed_degrees	Sum of cube degrees. See lal::properties::sum_powers_degrees for details.
sum_cubed_out_degrees	Sum of cube out-degrees. See lal::properties::sum_powers_out_degrees for details.
num_pairs_independent_edges	Size of the set \(Q(T)\) of this tree \(T\). See lal::properties::num_pairs_independent_edges for details.
head_initial	Headedness of the tree. In case the tree has only one vertex, outputs a NaN value. See lal::linarr::head_initial for details.
hubiness	Hubiness of the tree. In case a tree has 3 or less vertices the output is a 'NaN' value. See lal::properties::hubiness for details.
sum_hierarchical_distances	Sum of hierarchical distances of the tree. See lal::properties::sum_hierarchical_distances for details.
mean_hierarchical_distance	Mean hierarchical distance of the tree. In case a tree has 1 vertex the output is a 'NaN' value. See lal::properties::mean_hierarchical_distance for details.
tree_centre	Centre of the tree. This feature spans two columns, one for each possible central vertex. Each column contains an index: the first is always strictly less than the number of vertices, and the second is only valid when its value is strictly less than the number of vertices. See lal::properties::tree_centre for details on the definition of centre of a tree.
tree_centroid	Centroid of the tree. This feature spans two columns, one for each possible centroidal vertex. Each column contains an index: the first is always strictly less than the number of vertices, and the second is only valid when its value is strictly less than the number of vertices. See lal::properties::tree_centroid for details on the definition of centroid of a tree.
tree_diameter	Diameter of the tree. See lal::properties::tree_diameter for details.
tree_caterpillar_distance	Caterpillar distance of the tree. See lal::properties::tree_caterpillar_distance for details.
num_crossings	Number of edge crossings \(C\). See lal::linarr::num_crossings for details.
predicted_num_crossings	Prediction of the number of crossings \(C\). See lal::linarr::predicted_num_crossings for details.
exp_num_crossings	First moment of expectation of \(C\), \(E[C]\). See lal::properties::exp_num_crossings for details.
var_num_crossings	Variance of \(C\), \(V[C]\). See lal::properties::var_num_crossings for details.
z_score_num_crossings	z-score of \(C\), \(\frac{C - E[C]}{\sqrt{V[C]}}\). See lal::properties::var_num_crossings_tree for details on how the variance of \(C\), \(V[C]\), is calculated.
sum_edge_lengths	Sum of length of edges \(D\). See lal::linarr::sum_edge_lengths for details.
exp_sum_edge_lengths	Expectation of \(D\), \(E[D]\). See lal::properties::exp_sum_edge_lengths for details.
exp_sum_edge_lengths_bipartite	Expectation of \(D\) constrained to bipartite arrangements, \(E_{\mathrm{bip}}[D]\). See lal::properties::exp_sum_edge_lengths_bipartite for details.
exp_sum_edge_lengths_projective	Expectation of \(D\) constrained to projective arrangements, \(E_{\mathrm{pr}}[D]\). See lal::properties::exp_sum_edge_lengths_projective for details.
exp_sum_edge_lengths_planar	Expectation of \(D\) constrained to planar arrangements, \(E_{\mathrm{pl}}[D]\). See lal::properties::exp_sum_edge_lengths_planar for details.
var_sum_edge_lengths	Variance of \(D\), \(V[D]\). See lal::properties::var_sum_edge_lengths for details.
z_score_sum_edge_lengths	z-score of \(D\), \(\frac{D - E[D]}{\sqrt{V[D]}}\). See lal::properties::var_sum_edge_lengths for details on how the variance of \(D\), \(V[D]\), is calculated.
min_sum_edge_lengths	Unconstrained minimum sum of length of edges. See lal::linarr::algorithms_Dmin for details. The algorithm used is lal::linarr::algorithms_Dmin::Shiloach.
min_sum_edge_lengths_bipartite	Minimum sum of length of edges over bipartite arrangements. See lal::linarr::min_sum_edge_lengths_bipartite for details.
min_sum_edge_lengths_planar	Minimum sum of length of edges under the planarity constraint. See lal::linarr::min_sum_edge_lengths_planar for details.
min_sum_edge_lengths_projective	Minimum sum of length of edges under the planarity constraint. See lal::linarr::min_sum_edge_lengths_projective for details.
max_sum_edge_lengths	Maximum sum of length of edges over all arrangements. See lal::linarr::max_sum_edge_lengths_all for details.
max_sum_edge_lengths_1_thistle	Maximum sum of length of edges over arrangements with 1 thistle vertex. See lal::linarr::max_sum_edge_lengths_1_eq_thistle for details.
max_sum_edge_lengths_bipartite	Maximum sum of length of edges among bipartite arrangements. See lal::linarr::max_sum_edge_lengths_bipartite for details.
max_sum_edge_lengths_planar	Maximum sum of length of edges under the planarity constraint. See lal::linarr::max_sum_edge_lengths_planar for details.
max_sum_edge_lengths_projective	Maximum sum of length of edges under the planarity constraint. See lal::linarr::max_sum_edge_lengths_projective for details.
mean_dependency_distance	Mean dependency distance of the tree. In case a tree has 1 vertex the output is a 'NaN' value. See lal::linarr::mean_dependency_distance for details.
flux_max_weight	Maximum flux weight. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_mean_weight	Mean flux weight. This is the sum of weights averaged by the number of fluxes (the number of vertices of the tree minus 1). In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details on the definition of weight.
flux_min_weight	Minimum flux weight. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_max_left_span	Maximum left span. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_mean_left_span	Mean left span. This is the sum of left spans averaged by the number of fluxes (the number of vertices of the tree minus 1). In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details on the definition of left span.
flux_min_left_span	Minimum left span. In case the tree has 1 vertex, the output is a 'nan' value. See linarr::dependency_flux for details.
flux_max_right_span	Maximum right span. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_mean_right_span	Mean right span. This is the sum of right spans averaged by the number of fluxes (the number of vertices of the tree minus 1). In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details on the definition of right span.
flux_min_right_span	Minimum right span. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_max_size	Maximum flux size. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_mean_size	Mean flux size. This is the sum of flux sizes averaged by the number of fluxes (the number of vertices of the tree minus 1). In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details on the definition of flux size.
flux_min_size	Minimum flux size. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_max_RL_ratio	Maximum R/L ratio. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_mean_RL_ratio	Mean R/L ratio. This is the sum of R/L ratios averaged by the number of fluxes (the number of vertices of the tree minus 1). In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details on the definition of R/L ratio.
flux_min_RL_ratio	Minimum R/L ratio. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_max_WS_ratio	Maximum W/S ratio. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
flux_mean_WS_ratio	Mean W/S ratio. This is the sum of W/S ratios averaged by the number of fluxes (the number of vertices of the tree minus 1). In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details on the definition of W/S ratio.
flux_min_WS_ratio	Minimum W/S ratio. In case the tree has 1 vertex, the output is a 'nan' value. See lal::linarr::dependency_flux for details.
tree_type	The type of tree. This feature spans as many columns as types of trees are available in this library. Each column will contain either a 0 or a 1 depending on whether or not the tree can be classified into that type of tree. See lal::graphs::tree_type for a complete list of tree types.
syntactic_dependency_tree_class	The type of syntactic dependency structure. This feature spans as many columns as types of syntactic dependency structure are available in this library. Each column will contain either a 0 or a 1 depending on whether or not the tree can be classified into that syntactic dependency structure. See lal::linarr::syntactic_dependency_tree_type for a complete list of types.

treebank_file_error_type

enum class lal::io::treebank_file_error_type

strong

Possible errors that can arise while processing a collection.

There are several reasons why a treebank collection or a single treebank file could not be processed. Because of this, certain methods return one of these values instead of a plain 'false' value.

Enumerator
no_error	No error occurred. Returned by: lal::io::treebank_reader lal::io::treebank_processor lal::io::treebank_collection_reader lal::io::treebank_collection_processor
no_features	No features at all were given to the processor. Returned by: lal::io::treebank_processor lal::io::treebank_collection_processor
treebank_file_does_not_exist	A treebank was not found in disk. Returned by: lal::io::treebank_processor lal::io::treebank_collection_processor
treebank_file_could_not_be_opened	A treebank file could not be opened. Returned by: lal::io::treebank_reader lal::io::treebank_processor lal::io::treebank_collection_processor
output_file_could_not_be_opened	Output file could not be opened. Returned by: lal::io::treebank_processor lal::io::treebank_collection_processor
malformed_treebank_file	The treebank file contains errors that should be fixed. In this case, method lal::io::check_correctness_treebank should be run in order to obtain a report on the errors. Returned by: lal::io::treebank_processor
main_file_does_not_exist	Main file does not exist. Returned by: lal::io::treebank_collection_reader lal::io::treebank_collection_processor
main_file_could_not_be_opened	Main file could not be opened. Returned by: lal::io::treebank_collection_reader lal::io::treebank_collection_processor
output_directory_could_not_be_created	Output directory could not be created. If a directory output does not exist, the library will attempt to create it. If this fails then this error is returned. Returned by: lal::io::treebank_collection_processor.
output_join_file_could_not_be_opened	The file containing the result of processing a treebank collection could not be opened. Returned by: lal::io::treebank_collection_processor.
treebank_result_file_could_not_be_opened	The resulting file of processing a treebank could not be opened. Returned by: lal::io::treebank_collection_processor.
some_treebank_file_failed	Processing one or more of the treebanks failed. Returned by: lal::io::treebank_collection_processor.
malformed_treebank_collection	The treebank collection contains errors that should be fixed. In this case, method lal::io::check_correctness_treebank_collection should be run in order to obtain a report on the errors. Returned by: lal::io::treebank_collection_processor

Function Documentation

check_correctness_head_vector() [1/2]

std::vector< head_vector_error > lal::io::check_correctness_head_vector ( const head_vector & head_vector )

nodiscardnoexcept

Checks the correctness of a head vector.

Parameters

head_vector

A head vector.

Returns

A list of error messages.

check_correctness_head_vector() [2/2]

std::vector< head_vector_error > lal::io::check_correctness_head_vector ( const std::string & head_vector_str )

nodiscardnoexcept

Checks the correctness of a head vector.

The head vector is given in a string.

Parameters

head_vector_str

A string containing a head vector.

Returns

A list of error messages.

check_correctness_treebank()

treebank_file_report lal::io::check_correctness_treebank ( const std::string & treebank_filename )

nodiscardnoexcept

Checks the correctness of a treebank collection.

Parameters

treebank_filename

Name of the treebank file.

Returns

A list of errors.

check_correctness_treebank_collection()

treebank_collection_report lal::io::check_correctness_treebank_collection ( const std::string & main_file_name, const std::size_t n_threads = 1 )

nodiscardnoexcept

Checks the correctness of a treebank collection.

Parameters

main_file_name	Name of the main file.
n_threads	Number of threads to use.

Returns

A list of errors.

process_treebank()

treebank_file_error lal::io::process_treebank ( const std::string & treebank_file, const std::string & output_file )

inlinenodiscardnoexcept

Automatically process a treebank.

This function is an utility to process easily a single treebank file. This function uses the class lal::io::treebank_processor in order to process such a file. The default values of the processor are used, i.e., all features available in lal::io::treebank_feature_type are computed.

Parameters

treebank_file	The treebank file name.
output_file	The output file name.

Returns

A treebank error if any.

process_treebank_collection()

treebank_file_error lal::io::process_treebank_collection ( const std::string & treebank_collection_main_file, const std::string & output_directory, const std::size_t num_threads = 1 )

inlinenodiscardnoexcept

Automatically process a treebank collection.

This function is an utility to process easily a collection of treebank files. This function uses the class lal::io::treebank_collection_processor in order to process such a collection, with all its options set to their default value. The default options are:

• All features in lal::io::treebank_feature_type are computed,
• All files produced are joined into a single file,
• The individual files are deleted.

  Parameters

  treebank_collection_main_file	The main file of the treebank collection.
  output_directory	The output .
  num_threads	The number of threads.

  Returns

  A treebank error if any.

read_edge_list()

template<class graph_t , std::enable_if_t< std::is_base_of_v< graphs::graph, graph_t >, bool > = true>

std::optional< graph_t > lal::io::read_edge_list ( const std::string & filename, const bool norm = true, const bool check_norm = true )

inlinenodiscardnoexcept

Reads a graph in edge list format.

See File with edge list format for further details on the format.

This function calls lal::io::read_edge_list_undirected_graph, lal::io::read_edge_list_directed_graph, lal::io::read_edge_list_free_tree or lal::io::read_edge_list_rooted_tree depending on the type of the template parameter G.

Parameters

filename	Name of the file.
norm	Should the graph be normalized? See lal::graphs::graph::is_normalized()
check_norm	If the graph is not to be normalized check whether or not the graph read is normalized.

Template Parameters

graph_t

A graph type. A class that derives from lal::graphs::graph.

Returns

Nothing in case the file does not exist. A free graph if otherwise.

read_edge_list_directed_graph()

std::optional< graphs::directed_graph > lal::io::read_edge_list_directed_graph ( const std::string & filename, const bool norm = true, const bool check_norm = true )

nodiscardnoexcept

Reads a directed graph in edge list format.

See File with edge list format for further details on the format.

Parameters

filename	Name of the file.
norm	Should the graph be normalized? See lal::graphs::graph::is_normalized()
check_norm	If the graph is not to be normalized check whether or not the graph read is normalized.

Returns

Nothing in case the file does not exist. A free graph if otherwise.

read_edge_list_free_tree()

std::optional< graphs::free_tree > lal::io::read_edge_list_free_tree ( const std::string & filename, const bool norm = true, const bool check_norm = true )

nodiscardnoexcept

Reads a free tree in edge list format.

See File with edge list format for further details on the format.

Parameters

filename	Name of the file.
norm	Should the graph be normalized? See lal::graphs::graph::is_normalized()
check_norm	If the graph is not to be normalized check whether or not the graph read is normalized.

Returns

Nothing in case the file does not exist. A free graph if otherwise.

read_edge_list_rooted_tree()

std::optional< graphs::rooted_tree > lal::io::read_edge_list_rooted_tree ( const std::string & filename, const bool norm = true, const bool check_norm = true )

nodiscardnoexcept

Reads a rooted tree in edge list format.

See File with edge list format for further details on the format.

Parameters

filename	Name of the file.
norm	Should the graph be normalized? See lal::graphs::graph::is_normalized()
check_norm	If the graph is not to be normalized check whether or not the graph read is normalized.

Returns

Nothing in case the file does not exist. A free graph if otherwise.

read_edge_list_undirected_graph()

std::optional< graphs::undirected_graph > lal::io::read_edge_list_undirected_graph ( const std::string & filename, const bool norm = true, const bool check_norm = true )

nodiscardnoexcept

Reads a undirected graph in edge list format.

See File with edge list format for further details on the format.

Parameters

filename	Name of the file.
norm	Should the graph be normalized? See lal::graphs::graph::is_normalized()
check_norm	If the graph is not to be normalized check whether or not the graph read is normalized.

Returns

Nothing in case the file does not exist. A free graph if otherwise.

read_head_vector()

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

std::optional< tree_t > lal::io::read_head_vector ( const std::string & filename, const bool norm = true, const bool check_norm = true )

inlinenodiscardnoexcept

Reads a rooted tree in head vector format.

See Head vector for details on what a head vector is.

The current contents of the graph will be cleared and replaced by the contents of the file.

Parameters

filename	Name of the file.
norm	Should the graph be normalized? See lal::graphs::graph::is_normalized()
check_norm	If the graph is not to be normalized check whether or not the graph read is normalized.

Returns

Nothing in case the file does not exist. A free tree if otherwise.

read_head_vector_free_tree()

std::optional< graphs::free_tree > lal::io::read_head_vector_free_tree ( const std::string & filename, const bool norm = true, const bool check_norm = true )

nodiscardnoexcept

Reads a free tree in head vector format.

See Head vector for details on what a head vector is.

The current contents of the graph will be cleared and replaced by the contents of the file.

Parameters

filename	Name of the file.
norm	Should the tree be normalized? See lal::graphs::free_tree::is_normalized()
check_norm	If the graph is not to be normalized check whether or not the graph read is normalized.

Returns

Nothing in case the file does not exist. A free tree if otherwise.

read_head_vector_rooted_tree()

std::optional< graphs::rooted_tree > lal::io::read_head_vector_rooted_tree ( const std::string & filename, const bool norm = true, const bool check_norm = true )

nodiscardnoexcept

Reads a rooted tree in head vector format.

See Head vector for details on what a head vector is.

The current contents of the graph will be cleared and replaced by the contents of the file.

Parameters

filename	Name of the file.
norm	Should the graph be normalized? See lal::graphs::graph::is_normalized()
check_norm	If the graph is not to be normalized check whether or not the graph read is normalized.

Returns

Nothing in case the file does not exist. A free tree if otherwise.

treebank_feature_string()

std::string_view lal::io::treebank_feature_string ( const io::treebank_feature_type & tf )

inlineconstexprnoexcept

Converts a lal::io::treebank_feature_type value into a string.

Parameters

tf	A treebank feature.

Returns

A string used to format output files.

Variable Documentation

__treebank_feature_size

std::size_t lal::io::__treebank_feature_size

inlineconstexpr

Initial value:

=
    static_cast<std::size_t>(treebank_feature_type::__last_value)

The total number of features available.

This number equals the total amount of values within the enumeration lal::io::treebank_feature_type, except the last one (which should never be used).