fastoad.base.flight_point module¶

Structure for managing flight point data.

class fastoad.base.flight_point.FlightPoint(*args, **kwargs)[source]¶

Bases: fastoad.base.dict.DynamicAttributeDict

Class for storing data for one flight point.

An instance is a simple dict, but for convenience, each item can be accessed as an attribute (inspired by pandas DataFrames). Hence, one can write:

>>> fp = FlightPoint(speed=250., altitude=10000.)
>>> fp["speed"]
250.0
>>> fp2 = FlightPoint({"speed":150., "altitude":5000.})
>>> fp2.speed
250.0
>>> fp["mass"] = 70000.
>>> fp.mass
70000.0
>>> fp.mass = 50000.
>>> fp["mass"]
50000.0

Note: constructor will forbid usage of unknown keys as keyword argument, but other methods will allow them, while not making the matching between dict keys and attributes, hence:

>>> fp["foo"] = 42  # Ok
>>> bar = fp.foo  # raises exception !!!!
>>> fp.foo = 50  # allowed by Python
>>> # But inner dict is not affected:
>>> fp.foo
50
>>> fp["foo"]
42

This class is especially useful for generating pandas DataFrame: a pandas DataFrame can be generated from a list of dict… or a list of FlightPoint instances.

The set of dictionary keys that are mapped to instance attributes is given by the get_attribute_keys().

A dictionary class where keys can also be used as attributes.

The keys that can be used as attributes are defined using decorators AddKeyAttribute or SetKeyAttributes.

They can also be used as keyword arguments when instantiating this class.

Note

Using this class as a dict is useful when instantiating another dict or a pandas DataFrame, or instantiating from them. Direct interaction with DynamicAttributeDict instance should be done through attributes.

Example:

>>> @AddKeyAttributes({"foo": 0.0, "bar": None, "baz": 42.0})
... class MyDict(DynamicAttributeDict):
...     pass
...

>>> d = MyDict(foo=5, bar="aa")
>>> d.foo
5
>>> d.bar
'aa'
>>> d.baz  # returns the default value
42.0
>>> d["foo"] = 10.0  # can still be used as a dict
>>> d.foo  # but change are propagated to/from the matching attribute
10.0
>>> d.foo = np.nan  # setting None or numpy.nan returns to default value
>>> d["foo"]
0.0
>>> d.foo # But the attribute will now return the default value
0.0
>>> d.bar = None  # If default value is None, setting None or numpy.nan deletes the key.
>>> # d["bar"]  #would trigger a key error
>>> d.bar # But the attribute will return None

Parameters

args – a dict-like object where all keys are contained in attribute_keys
kwargs – argument keywords must be names contained in attribute_keys

property CD¶: Drag coeffient.

property CL¶: Lift coeffient.

property acceleration¶: Acceleration value in m/s**2.

property altitude¶: Altitude in meters.

property drag¶: Aircraft drag in Newtons.

property engine_setting¶: Engine setting (see EngineSetting).

property equivalent_airspeed¶: Equivalent airspeed (EAS) in m/s.

classmethod get_attribute_keys()¶

Returns: list of attributes paired to dict key.

property ground_distance¶: Covered ground distance in meters.

property mach¶: Mach number.

property mass¶: Mass in kg.

property name¶: Name of current phase.

property sfc¶: Specific Fuel Consumption in kg/N/s.

property slope_angle¶: Slope angle in radians.

property thrust¶: Thrust in Newtons.

property thrust_is_regulated¶: Boolean. If True, propulsion should match the thrust value. If False, propulsion should match thrust rate.

property thrust_rate¶: Thrust rate (between 0. and 1.)

property time¶: Time in seconds.

property true_airspeed¶: True airspeed (TAS) in m/s.