Vector support in ports?

[seanmcleod70]

@milanofthe Matlab/Simulink has support for vectors in addition to scalars in ports, for example:

Are there plans to add support for vectors as elements of an input/output port?

[seanmcleod70]

Couple of examples so far in terms of implementing Matlab/Simulink block equivalents where the question of vectors arises.

class DynamicPressure(Function):
    """Calculate the dynamic pressure, given the velocity and air density.
    """

    input_port_labels = {
        "V1": 0,
        "V2": 1,
        "V3": 2,
        "rho": 3
    }

    output_port_labels = {
        "q": 0
    }

    def __init__(self):
        super().__init__(func=self._eval)
    
    def _eval(self, V1, V2, V3, density):
        V_mag = math.sqrt(V1**2 + V2**2 + V3**2)
        return 0.5 * density * V_mag**2


class IncidenceSideslipAirspeed(Function):
    """Calculates the angles between the velocity vector and the body and the total airspeed, 
    given the velocity components in the body-fixed coordinate frame. 
    """

    input_port_labels = {
        "u": 0,
        "v": 1,
        "w": 2
    }

    output_port_labels = {
        "alpha": 0,
        "beta": 1,
        "V": 2
    }

    def __init__(self):
        super().__init__(func=self._eval)

    def _eval(self, u, v, w):
        V = math.sqrt(u**2 + v**2 + w**2)
        alpha = math.atan2(w, u) if u != 0 else 0
        uw2 = u**2 + w**2
        beta = math.atan2(v / math.sqrt(uw2)) if uw2 != 0 else 0
        return (alpha, beta, V)


class CrossProduct(Function):
    """Calculate the cross product of two 3D vectors.
    """
    input_port_labels = {
        "A1": 0,
        "A2": 1,
        "A3": 2,
        "B1": 3,
        "B2": 4,
        "B3": 5
    }

    output_port_labels = {
        "C1": 0,
        "C2": 1,
        "C3": 2
    }

    def __init__(self):
        super().__init__(func=self._eval)

    def _eval(self, A1, A2, A3, B1, B2, B3):
        A = np.array([A1, A2, A3])
        B = np.array([B1, B2, B3])
        C = np.cross(A, B)
        return (C[0], C[1], C[2])

[seanmcleod70]

Also the ability to operate on a scalar or a vector/array. For example from Matlab/Simulink Angle Conversion block.

So convert a scalar from/to deg/rad or a whole array depending on what is connected to the port.

class AngleConversion(Function):
    """Convert an angle from degrees to radians or from radians to degrees.
    """
    input_port_labels = {
        "angle": 0,
    }

    output_port_labels = {
        "angle": 0
    }

    def __init__(self, input_units="deg"):      # TODO String, or a global enum of units?
        super().__init__(func=self._eval)
        self.input_units = input_units

    def _eval(self, angle):
        if self.input_units == "deg":
            return math.radians(angle)
        elif self.input_units == "rad":
            return math.degrees(angle)
        raise ValueError("Invalid input_units. Must be 'deg' or 'rad'.")