Vector

Vectors class they are like segments, but with a given direction

Vector

Bases: Segment, DirectedLinearEntity

Vector class to manipulate vector which can be seen as Segment with direction

Source code in otary/geometry/discrete/linear/directed/vector.py

class Vector(Segment, DirectedLinearEntity):
    """Vector class to manipulate vector which can be seen as Segment with direction"""

    @classmethod
    def from_single_point(cls, point: NDArray) -> Vector:
        """Get vector that goes from [0, 0] to point

        Args:
            point (NDArray): point of shape 2

        Returns:
            Vector: new vector object
        """
        return cls(points=[[0, 0], point])

    @property
    def cardinal_degree(self) -> float:
        """Returns the cardinal degree of the vector in the cv2 space.
        We consider the top of the image to point toward the north as default and thus
        represent the cardinal degree value 0 mod 360.

        Returns:
            float: cardinal degree
        """
        angle = self.slope_angle(degree=True, is_y_axis_down=True)

        # if angle is negative
        is_neg_sign_angle = bool(np.sign(angle) - 1)
        if is_neg_sign_angle:
            angle = 90 + np.abs(angle)
        else:
            angle = 90 - angle

        # if vector points towards west
        if self.is_x_first_pt_gt_x_last_pt:
            angle += 180

        cardinal_degree = np.mod(360 + angle, 360)  # avoid negative value case
        return cardinal_degree

    @property
    def coordinates_shift(self) -> NDArray:
        """Return the vector as a single point (x1-x0, y1-y0)

        Returns:
            NDArray: coordinates shift
        """
        return self.origin[1]

    @property
    def normalized(self) -> NDArray:
        """Nornalized vector

        Returns:
            NDArray: normalized vector
        """
        return self.coordinates_shift / np.linalg.norm(self.coordinates_shift) + 1e-9

    def rescale_head(self, scale: float) -> Vector:
        """Rescale the head part of the vector without moving the first point.
        This method only updates the second point that composes the vector.

        Args:
            scale (float): scale factor

        Returns:
            Vector: scaled vector
        """
        self.asarray = (self.asarray - self.tail) * scale + self.tail
        return self

cardinal_degree property

Returns the cardinal degree of the vector in the cv2 space. We consider the top of the image to point toward the north as default and thus represent the cardinal degree value 0 mod 360.

Returns:

Name	Type	Description
float	float	cardinal degree

coordinates_shift property

Return the vector as a single point (x1-x0, y1-y0)

Returns:

Name	Type	Description
NDArray	NDArray	coordinates shift

normalized property

Nornalized vector

Returns:

Name	Type	Description
NDArray	NDArray	normalized vector

from_single_point(point) classmethod

Get vector that goes from [0, 0] to point

Parameters:

Name	Type	Description	Default
point	NDArray	point of shape 2	required

Returns:

Name	Type	Description
Vector	Vector	new vector object

Source code in otary/geometry/discrete/linear/directed/vector.py

@classmethod
def from_single_point(cls, point: NDArray) -> Vector:
    """Get vector that goes from [0, 0] to point

    Args:
        point (NDArray): point of shape 2

    Returns:
        Vector: new vector object
    """
    return cls(points=[[0, 0], point])

rescale_head(scale)

Rescale the head part of the vector without moving the first point. This method only updates the second point that composes the vector.

Parameters:

Name	Type	Description	Default
scale	float	scale factor	required

Returns:

Name	Type	Description
Vector	Vector	scaled vector

Source code in otary/geometry/discrete/linear/directed/vector.py

def rescale_head(self, scale: float) -> Vector:
    """Rescale the head part of the vector without moving the first point.
    This method only updates the second point that composes the vector.

    Args:
        scale (float): scale factor

    Returns:
        Vector: scaled vector
    """
    self.asarray = (self.asarray - self.tail) * scale + self.tail
    return self