fcapy.algorithms.lattice_construction

This module contains a number of function which take a set of formal (or pattern) concepts and return its children_dict i.e. the order of given concepts in the form {parent_concept_index: child_concept_index}.

Parent_concept is a concept which is bigger (or more general) than the child concept and there is no other concept between these two.

Functions

`add_concept`(new_concept, concepts, ...[, ...])	Add `new_concept` into a set of `concepts` regarding its subconcept relation
`complete_comparison`(concepts[, ...])	Return a dict with subconcepts relation on given `concepts`.
`construct_lattice_by_spanning_tree`(concepts)	Return a dict with subconcepts relation on given `concepts`.
`construct_lattice_from_spanning_tree`(...[, ...])	Return a dict with subconcepts relation on given concepts from given spanning tree of the relation.
`construct_lattice_from_spanning_tree_parallel`(...)	Return a dict with subconcepts relation on given `concepts` from given spanning tree of the relation.
`construct_spanning_tree`(concepts[, ...])	Return a spanning tree of subconcepts relation on given `concepts`.
`remove_concept`(concept_i, concepts, ...[, ...])	Remove a `concept_i` from a set of `concepts` regarding its subconcept relation

fcapy.algorithms.lattice_construction.add_concept(new_concept, concepts, subconcepts_dict, superconcepts_dict, top_concept_i=None, bottom_concept_i=None, inplace=True)

Add new_concept into a set of concepts regarding its subconcept relation

Parameters

new_concept (FormalConcept or PatternConcept) – A concept to add
concepts (list of FormalConcept or PatternConcept) – A list of concepts to add a new_concept to
subconcepts_dict (dict of {int: int}) – A dict of the current subconcept relation of the concepts
superconcepts_dict (dict of {int: int}) – A dict of the current superconcept relation of the concepts
top_concept_i (int) – An index of the top (biggest) concept from concepts
bottom_concept_i (int) – An index of the bottom (smallest) concept from concepts
inplace (bool) – A flag whether to modify the concepts list inplace or create a new one

Returns

concepts (list of FormalConcept or PatternConcept) – A modified list of concepts
children_dict (dict of {int: int}) – A dict of modified subconcept relation of returned concepts
parents_dict (dict of {int: int}) – A dict of modified superconcept relation of returned concepts
top_concept (int) – An index of the top (biggest) concept of returned concepts
bottom_concept (int) – An index of the bottom (smallest) concept of returned concepts

fcapy.algorithms.lattice_construction.complete_comparison(concepts: Collection[FormalConcept], is_concepts_sorted: bool = False, n_jobs: int = 1, use_tqdm: bool = False)

Return a dict with subconcepts relation on given concepts. A slow but accurate bruteforce method

Parameters

concepts (list of FormalConcept or PatternConcept) – A list of concepts to compare
is_concepts_sorted (bool) – A flag whether the set of concepts is topologically sorted or it should be sorted inside the function
n_jobs (int) – A number of parallel jobs to run. WARNING: It is more efficient to run just one job for some reason
use_tqdm (bool) – A flag whether to visualize the progress of the algorithm with tqdm bar or not

Returns

children_dict – A dict of indexes with subconcept relation on the given concepts (of type {parent_concept_index: child_concept_index})

Return type

dict

fcapy.algorithms.lattice_construction.construct_lattice_by_spanning_tree(concepts, is_concepts_sorted=False, n_jobs=1, use_tqdm=False)

Return a dict with subconcepts relation on given concepts. Uses spanning tree approach to fasten the computation

Parameters

concepts (list of FormalConcept or PatternConcept) – A list of concepts to compare
is_concepts_sorted (bool) – A flag whether the set of concepts is topologically sorted or it should be sorted inside the function
n_jobs (int) – A number of parallel jobs to run. WARNING: It is more efficient to run just one job for some reason
use_tqdm (bool) – A flag whether to visualize the progress of the algorithm with tqdm bar or not

Returns

children_dict – A dict of indexes with subconcept relation on the given concepts (of type {parent_concept_index: child_concept_index})

Return type

dict

fcapy.algorithms.lattice_construction.construct_lattice_from_spanning_tree(concepts, sptree_chains, is_concepts_sorted=False, use_tqdm=False)

Return a dict with subconcepts relation on given concepts from given spanning tree of the relation.

Parameters

concepts (list of FormalConcept or PatternConcept) – A list of concepts to compare
sptree_chains (list of list of int) – A list of chains of a spanning tree of concepts subconcept relation. Can be constructed with ConceptLattice._get_chains(…) method
is_concepts_sorted (boot) – A flag whether the set of concepts is topologically sorted or it should be sorted inside the function
use_tqdm (bool) – A flag whether to visualize the progress of the algorithm with tqdm bar or not

Returns

children_dict – A dict of indexes with subconcept relation on the given concepts (of type {parent_concept_index: child_concept_index})

Return type

dict

fcapy.algorithms.lattice_construction.construct_lattice_from_spanning_tree_parallel(concepts, sptree_chains, is_concepts_sorted=False, n_jobs=1)

Return a dict with subconcepts relation on given concepts from given spanning tree of the relation.

WARNING: This parallelized function works slower than the original construct_lattice_from_spanning_tree function.

Parameters

concepts (list of FormalConcept or PatternConcept) – A list of concepts to compare
sptree_chains (list of list of int) – A list of chains of a spanning tree of concepts subconcept relation. Can be constructed with ConceptLattice._get_chains(...) method
is_concepts_sorted (boot) – A flag whether the set of concepts is topologically sorted or it should be sorted inside the function
n_jobs (int) – A number of parallel jobs to run.

Returns

children_dict – A dict of indexes with subconcept relation on the given concepts (of type {parent_concept_index: child_concept_index})

Return type

dict

fcapy.algorithms.lattice_construction.construct_spanning_tree(concepts, is_concepts_sorted=False, use_tqdm=False)

Return a spanning tree of subconcepts relation on given concepts.

A spanning tree means that for each concept from concepts we look for one parent concept only (even if there are actually many of them)

Parameters

concepts (list of FormalConcept or PatternConcept) – A list of concepts to compare
is_concepts_sorted (boot) – A flag whether the set of concepts is topologically sorted or it should be sorted inside the function
use_tqdm (bool) – A flag whether to visualize the progress of the algorithm with tqdm bar or not

Returns

children_dict – A dict of indexes with spanning tree of subconcept relation on the given concepts (of type {parent_concept_index: child_concept_index})

Return type

dict

fcapy.algorithms.lattice_construction.remove_concept(concept_i, concepts, subconcepts_dict, superconcepts_dict, top_concept_i=None, bottom_concept_i=None, inplace=True)

Remove a concept_i from a set of concepts regarding its subconcept relation

Parameters

concept_i (int) – An index of concept to be removed
concepts (list of FormalConcept or PatternConcept) – A list of concepts to remove a concept_i from
subconcepts_dict (dict of {int: int}) – A dict of the current subconcept relation of the concepts
superconcepts_dict (dict of {int: int}) – A dict of the current superconcept relation of the concepts
top_concept_i (int) – An index of the top (biggest) concept from concepts
bottom_concept_i (int) – An index of the bottom (smallest) concept from concepts
inplace (bool) – A flag whether to modify the concepts list inplace or create a new one

Returns

concepts (list of FormalConcept or PatternConcept) – A modified list of concepts
children_dict (dict of {int: int}) – A dict of modified subconcept relation of returned concepts
parents_dict (dict of {int: int}) – A dict of modified superconcept relation of returned concepts
top_concept (int) – An index of the top (biggest) concept of returned concepts
bottom_concept (int) – An index of the bottom (smallest) concept of returned concepts