def compute_from(self, start: FlightPoint) -> pd.DataFrame:
self.complete_flight_point(
start) # needed to ensure all speed values are computed.
if self.target.altitude:
if isinstance(self.target.altitude, str):
# Target altitude will be modified along the process, so we keep track
# of the original order in target CL, that is not used otherwise.
self.target.CL = self.target.altitude # pylint: disable=invalid-name
# let's put a numerical, negative value in self.target.altitude to
# ensure there will be no problem in self._get_distance_to_target()
self.target.altitude = -1000.0
self.interrupt_if_getting_further_from_target = False
else:
# Target altitude is fixed, back to original settings (in case
# this instance is used more than once)
self.target.CL = None
self.interrupt_if_getting_further_from_target = True
atm = AtmosphereSI(start.altitude)
if self.target.equivalent_airspeed == self.CONSTANT_VALUE:
start.true_airspeed = atm.get_true_airspeed(
start.equivalent_airspeed)
elif self.target.mach == self.CONSTANT_VALUE:
start.true_airspeed = start.mach * atm.speed_of_sound
return super().compute_from(start)
def _get_distance_to_target(self,
flight_points: List[FlightPoint]) -> float:
current = flight_points[-1]
# Max flight level is first priority
max_authorized_altitude = self.maximum_flight_level * 100.0 * foot
if current.altitude >= max_authorized_altitude:
return max_authorized_altitude - current.altitude
if self.target.CL:
# Optimal altitude is based on a target Mach number, though target speed
# may be specified as TAS or EAS. If so, Mach number has to be computed
# for target altitude and speed.
# First, as target speed is expected to be set to self.CONSTANT_VALUE for one
# parameter. Let's get the real value from start point.
target_speed = copy(self.target)
for speed_param in [
"true_airspeed", "equivalent_airspeed", "mach"
]:
if isinstance(getattr(target_speed, speed_param), str):
setattr(target_speed, speed_param,
getattr(flight_points[0], speed_param))
# Now, let's compute target Mach number
atm = AtmosphereSI(max(self.target.altitude, current.altitude))
if target_speed.equivalent_airspeed:
target_speed.true_airspeed = atm.get_true_airspeed(
target_speed.equivalent_airspeed)
if target_speed.true_airspeed:
target_speed.mach = target_speed.true_airspeed / atm.speed_of_sound
# Now we compute optimal altitude
optimal_altitude = self._get_optimal_altitude(
current.mass, target_speed.mach, current.altitude)
if self.target.CL == self.OPTIMAL_ALTITUDE:
self.target.altitude = optimal_altitude
else: # self.target.CL == self.OPTIMAL_FLIGHT_LEVEL:
self.target.altitude = get_closest_flight_level(
optimal_altitude, up_direction=False)
if self.target.altitude is not None:
return self.target.altitude - current.altitude
if self.target.true_airspeed and self.target.true_airspeed != self.CONSTANT_VALUE:
return self.target.true_airspeed - current.true_airspeed
if (self.target.equivalent_airspeed
and self.target.equivalent_airspeed != self.CONSTANT_VALUE):
return self.target.equivalent_airspeed - current.equivalent_airspeed
if self.target.mach is not None and self.target.mach != self.CONSTANT_VALUE:
return self.target.mach - current.mach
raise FastFlightSegmentIncompleteFlightPoint(
"No valid target definition for altitude change.")
def compute_from(self, start: FlightPoint) -> pd.DataFrame:
start = FlightPoint(start)
self.complete_flight_point(start) # needed to ensure all speed values are computed.
if self.target.altitude and self.target.altitude < 0.0:
# Target altitude will be modified along the process, so we keep track
# of the original order in target CL, that is not used otherwise.
self.target.CL = self.target.altitude
self.interrupt_if_getting_further_from_target = False
atm = AtmosphereSI(start.altitude)
if self.target.equivalent_airspeed == "constant":
start.true_airspeed = atm.get_true_airspeed(start.equivalent_airspeed)
elif self.target.mach == "constant":
start.true_airspeed = start.mach * atm.speed_of_sound
return super().compute_from(start)
def _get_distance_to_target(self, flight_points: List[FlightPoint]) -> bool:
current = flight_points[-1]
if self.target.CL:
# Optimal altitude is based on a target Mach number, though target speed
# may be specified as TAS or EAS. If so, Mach number has to be computed
# for target altitude and speed.
# First, as target speed is expected to be set to "constant" for one
# parameter. Let's get the real value from start point.
target_speed = FlightPoint(self.target)
for speed_param in ["true_airspeed", "equivalent_airspeed", "mach"]:
if isinstance(target_speed.get(speed_param), str):
target_speed[speed_param] = flight_points[0][speed_param]
# Now, let's compute target Mach number
atm = AtmosphereSI(max(self.target.altitude, current.altitude))
if target_speed.equivalent_airspeed:
target_speed.true_airspeed = atm.get_true_airspeed(target_speed.equivalent_airspeed)
if target_speed.true_airspeed:
target_speed.mach = target_speed.true_airspeed / atm.speed_of_sound
# Mach number has to be capped by self.maximum_mach
target_mach = min(target_speed.mach, self.maximum_mach)
# Now we compute optimal altitude
optimal_altitude = self._get_optimal_altitude(
current.mass, target_mach, current.altitude
)
if self.target.CL == self.OPTIMAL_ALTITUDE:
self.target.altitude = optimal_altitude
else: # self.target.CL == self.OPTIMAL_FLIGHT_LEVEL:
flight_level = 1000 * foot
self.target.altitude = flight_level * np.floor(optimal_altitude / flight_level)
if self.target.altitude:
return self.target.altitude - current.altitude
elif self.target.true_airspeed:
return self.target.true_airspeed - current.true_airspeed
elif self.target.equivalent_airspeed:
return self.target.equivalent_airspeed - current.equivalent_airspeed
elif self.target.mach:
return self.target.mach - current.mach
def _complete_speed_values(flight_point: FlightPoint):
"""
Computes consistent values between TAS, EAS and Mach, assuming one of them is defined.
"""
atm = AtmosphereSI(flight_point.altitude)
if flight_point.true_airspeed is None:
if flight_point.mach is not None:
flight_point.true_airspeed = flight_point.mach * atm.speed_of_sound
elif flight_point.equivalent_airspeed is not None:
flight_point.true_airspeed = atm.get_true_airspeed(
flight_point.equivalent_airspeed)
else:
raise FastFlightSegmentIncompleteFlightPoint(
"Flight point should be defined for true_airspeed, "
"equivalent_airspeed, or mach.")
if flight_point.mach is None:
flight_point.mach = flight_point.true_airspeed / atm.speed_of_sound
if flight_point.equivalent_airspeed is None:
flight_point.equivalent_airspeed = atm.get_equivalent_airspeed(
flight_point.true_airspeed)