Source code for pm4py.objects.transition_system.utils

'''
    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.transition_system import obj


[docs]def add_arc_from_to(name, fr, to, ts, data=None): """ Adds a transition from a state to another state in some transition system. Assumes from and to are in the transition system! Parameters ---------- name: name of the transition fr: state from to: state to ts: transition system to use data: data associated to the Transition System Returns ------- None """ tran = obj.TransitionSystem.Transition(name, fr, to, data) ts.transitions.add(tran) fr.outgoing.add(tran) to.incoming.add(tran)
[docs]def remove_arc_from_to(name, fr, to, ts): """ Removes a transition with a specific name from a state to another state in some transition system. Assumes from and to are in the transition system! Parameters ---------- name: name of the transition fr: state from to: state to ts: transition system to use Returns ------- None """ ts.transitions = [t for t in ts.transitions if t.name != name] fr.outgoing = [t for t in fr.outgoing if t.name != name] to.incoming = [t for t in to.incoming if t.name != name]
[docs]def remove_all_arcs_from_to(fr, to, ts): """ Removes all transitions from a state to another state in some transition system. Assumes from and to are in the transition system! Parameters ---------- fr: state from to: state to ts: transition system to use Returns ------- None """ names_transitions_to_delete = [t.name for t in ts.transitions if t in fr.outgoing and t in to.incoming] ts.transitions = set([t for t in ts.transitions if t.name not in names_transitions_to_delete]) fr.outgoing = set([t for t in fr.outgoing if t.name not in names_transitions_to_delete]) to.incoming = set([t for t in to.incoming if t.name not in names_transitions_to_delete])
[docs]def transitive_reduction(ts): """ Computes the transitive reduction of an acyclic transition system. Assumes the transition system in input to be acyclic. Parameters ---------- ts: acyclic transition system to use Returns ------- None """ def check(this_state, this_child, this_done): if this_child not in this_done: child_children = [tr.to_state for tr in ts.transitions if tr in this_child.outgoing] for child_child in child_children: remove_all_arcs_from_to(this_state, child_child, ts) check(this_state, child_child, this_done) this_done.add(this_child) for state in ts.states: done = set() children = [tr.to_state for tr in ts.transitions if tr in state.outgoing] for child in children: check(state, child, done)