def did_infection_after_marcov(self) -> bool:
if self.infection_occurred is None:
prb_infection = self.prob_infection
prb_infection *= self.config.rate_pessimism_factor
self.infection_occurred = marcov_binary(self.prob_infection)
return self.infection_occurred
def infect(self, person: Person, day: int, cause: str) -> None:
person.infected_by = cause
person.infected_on = day
person.symptomatic = marcov_binary(
self.config.symptomatic_dist().sample())
symptoms_start = person.infected_on + self.config.days_to_symptoms_dist(
).sample() # no symptoms is asymptomatic, but still used later
contagious_offset = self.config.contagious_offset_rel_symptoms(
person.symptomatic).sample()
contagious_start = symptoms_start + contagious_offset
if contagious_start <= day:
contagious_start = day + 1
person.contagious_from_inc = contagious_start
person.contagious_duration = self.config.contagious_duration_dist(
person.symptomatic).sample()
person.contagious_to_inc = person.contagious_from_inc + person.contagious_duration - 1
if person.symptomatic:
person.symptoms_start = symptoms_start
person.warn_potential_infection_on(
person.symptoms_start -
self.config.warn_interactions_days_before_symptoms,
person.symptoms_start)
def __a_infected_b_after_marcov(self, pa: Person, pb: Person) -> bool:
if pa.id == pb.id:
return False
if pa.practically_contagious(self.day.sample()):
prb_infection = self.prob_infection
prb_infection *= self.config.rate_pessimism_factor
if not pa.symptomatic:
prb_infection *= self.config.asymptomatic_infectious_factor
if prb_infection > 1:
prb_infection = 1
return marcov_binary(prb_infection)
return False
def maybe_infect_person(self, person: Person) -> tuple[bool, str]:
if person.is_infected_on_day(self.day):
return False, "already infected"
if marcov_binary(person.base_day_rate.sample()):
return True, "base:0"
for evt in person.get_events_after_marcov(self.day):
if evt.did_infection_after_marcov():
return True, f"event:{evt.description}"
for inter in person.get_interactions_after_marcov(self.day):
if inter.was_person_infected_after_marcov(person):
return True, f"interaction:{inter.description}"
return False, "not infected"
def did_occur_after_marcov(self) -> bool:
if self.__event_occurred is None:
self.__event_occurred = marcov_binary(self.probability_occurring)
return self.__event_occurred
def is_trustworthy(self) -> bool:
if self._is_trustworthy is None:
self._is_trustworthy = marcov_binary(self.trustworthy_prb)
return self._is_trustworthy
def start_and_propagate(self, num_days) -> None:
for person in self.people.values():
if marcov_binary(person.starting_infected_prb):
self.infect(person, 0, "started-infected")
self.propagate(num_days)