'''
This file is part of PM4Py (More Info: https://pm4py.fit.fraunhofer.de).
PM4Py is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
PM4Py is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with PM4Py. If not, see <https://www.gnu.org/licenses/>.
'''
from pm4py.objects.ocel.obj import OCEL
from typing import Optional, Dict, Any, Set, Tuple
from copy import copy
[docs]def apply(ocel: OCEL, parameters: Optional[Dict[Any, Any]] = None) -> Set[Tuple[str, str]]:
"""
Calculates the object descendants graph.
Two objects o1 and o2, both related to an event e, are connected if:
- e is the last event of the lifecycle of o1
- e is the first event of the lifecycle of o2
Parameters
-----------------
ocel
Object-centric event log
parameters
Parameters of the algorithm
Returns
-----------------
object_inheritance_graph
Object inheritance graph (directed)
"""
if parameters is None:
parameters = {}
graph = set()
ordered_events = list(ocel.events[ocel.event_id_column])
ev_rel_obj = ocel.relations.groupby(ocel.event_id_column)[ocel.object_id_column].apply(list).to_dict()
last_event_per_obj = {}
set_objects = set()
ordered_events_revert = copy(ordered_events)
ordered_events_revert.reverse()
for ev in ordered_events_revert:
rel_obj = ev_rel_obj[ev]
rel_obj_seen = {x for x in rel_obj if x in set_objects}
rel_obj_unseen = {x for x in rel_obj if x not in rel_obj_seen}
for obj in rel_obj_unseen:
last_event_per_obj[obj] = ev
set_objects.add(obj)
set_objects = set()
for ev in ordered_events:
rel_obj = ev_rel_obj[ev]
rel_obj_seen = {x for x in rel_obj if x in set_objects}
rel_obj_unseen = {x for x in rel_obj if x not in rel_obj_seen}
rel_obj_last = {x for x in rel_obj if last_event_per_obj[x] == ev}
for o2 in rel_obj_unseen:
for o1 in rel_obj_last:
if o1 != o2:
graph.add((o1, o2))
set_objects.add(o2)
graph_it = list(graph)
for el in graph_it:
if (el[1], el[0]) in graph:
graph.remove((el[0], el[1]))
graph.remove((el[1], el[0]))
return graph