Python Quaternion.getI方法代码示例

# 需要导入模块: from quaternion import Quaternion [as 别名]
# 或者: from quaternion.Quaternion import getI [as 别名]
 print("j*j = {0}".format(j*j))
 print("k*k = {0}".format(k*k))
 print()
 
 print("Products of components:")
 print("o*i = {0}\ti*o = {1}".format(o*i, i*o))
 print("o*j = {0}\tj*o = {1}".format(o*j, j*o))
 print("o*k = {0}\tk*o = {1}".format(o*k, k*o))
 print("i*j = {0}\tj*i = {1}".format(i*j, j*i))
 print("i*k = {0}\tk*i = {1}".format(i*k, k*i))
 print("j*k = {0}\tk*j = {1}".format(j*k, k*j))
 print()
 
 p = Quaternion(i)
 p.setScalar(-3).setJ(2).setK(-1)
 print("p=({0}, {1}, {2}, {3})".format(p.getScalar(), p.getI(), p.getJ(), p.getK()))
 # sqrt(15) = 3.87298
 print("||p|| = {0} (correct: 3.87298)".format(p.norm()))
 
 q = p.reciprocal()
 qc = "-0.2-0.0666666666667i-0.133333333333j+0.0666666666667k"
 
 print("p**(-1) = {0}\n(correct: {1})".format(q, qc))
 print("p*p**(-1) = {0}".format(p*q)) 
 print("p**(-1)*p = {0}".format(q*p))
 print()
 
 q = Quaternion(1, -2, 3, -4)
 print("q = {0}".format(q))
 print("p+q = {0}".format(p+q))
 print("p-q = {0}".format(p-q))

# 需要导入模块: from quaternion import Quaternion [as 别名]
# 或者: from quaternion.Quaternion import getI [as 别名]
class Rotation:
    """
    3D rotation around an axis, based on quaternion arithmetics.
    
    For the mathematical background about quaternion based rotation, see
    http://en.wikipedia.org/wiki/Quaternions_and_spatial_rotation
    """

    # Private internal instance members:
    # __r - a vector representing the axis of ratoation (Point3D)
    # __theta - angle of rotation (in radians)
    # __q - roatation quaternion

    def __init__(self, rx=0.0, ry=0.0, rz=0.0, angle=0.0):
        """
        A "constructor" that initializes an object.__class__
        
        Input:
        - rx - x - component of the vector (default: 0)
        - ry - y - component of the vector (default: 0)
        - rz - z - component of the vector (default: 0)
        - angle - angle of rotation in radians (default: 0)
        
        'rx' may also be an instance of a Point3D. In this case, ry and rz
        are ignored and rx's components are copied into this object.
        
        Note that the vector will automatically be converted into a unit vector.
        
        A RotationException is raised if input arguments are of invalid types.
        """
        if not InstanceCheck.isFloat(angle):
            raise RotationException("Angle must be a float value")

        self.__theta = angle
        self.setAxis(rx, ry, rz)

    def setAxis(self, rx=0.0, ry=0.0, rz=0.0):
        """
        Enters a new vector of the rotation. Rotation angle remains unmodified.
        
        Input:
        - rx - x - component of the vector (default: 0)
        - ry - y - component of the vector (default: 0)
        - rz - z - component of the vector (default: 0)
        
        'rx' may also be an instance of a Point3D. In this case, ry and rz
        are ignored and rx's components are copied into this object.
        
        Note that the vector will automatically be converted into a unit vector.
        
        A RotationException is raised if input arguments are of invalid types.
        """
        try:
            self.__r = Point3D(rx, ry, rz)
        except PointException:
            raise RotationException("Invalid input argument")

        self.__update()

    def setAngle(self, angle=0.0):
        """
        Sets a new angle of rotation. 
        Rotation vector's components remain unmodified.
        
        Input:
        - angle - angle of rotation in radians (default: 0)
        
        A RotationException is raised if 'angle' is not a float or integer value.
        """
        if not InstanceCheck.isFloat(angle):
            raise RotationException("Angle must be float value")

        self.__theta = angle
        self.__update()

    def __update(self):
        # A private method, called after any rotation component (vector or angle)
        # is modified. It normalizes the vector (its length must be 1),
        # updates self.__r and recalculates the rotation quaternion (self.__q).
        #
        # A RotationException is raised if any quaternion operation fails.
        try:
            # copy vector's components into the quaternion and normalize it:
            self.__q = Quaternion(0.0, self.__r.x, self.__r.y, self.__r.z).unit()

            # update __r to a unit vector
            self.__r.x = self.__q.getI()
            self.__r.y = self.__q.getJ()
            self.__r.z = self.__q.getK()

            # Calculate the rotation quaternion, depending on rot. vector and angle:
            # For more info, see::
            # http://en.wikipedia.org/wiki/Quaternions_and_spatial_rotation
            self.__q *= math.sin(0.5 * self.__theta)
            self.__q += math.cos(0.5 * self.__theta)

        except QuaternionException as qex:
            raise RotationException("Could not generate a rotation quaternion: '{0}'".format(qex))

    def getAxis(self, factor=1.0):
#.........这里部分代码省略.........