qiskit/quantum_info/operators/quaternion.py
def to_matrix(self):
        """Converts a unit-length quaternion to a rotation matrix.

        Returns:
            ndarray: Rotation matrix.
        """
        w, x, y, z = self.normalize().data  # pylint: disable=C0103
        mat = np.array([
            [1-2*y**2-2*z**2, 2*x*y-2*z*w, 2*x*z+2*y*w],
            [2*x*y+2*z*w, 1-2*x**2-2*z**2, 2*y*z-2*x*w],
            [2*x*z-2*y*w, 2*y*z+2*x*w, 1-2*x**2-2*y**2]
        ], dtype=float)
        return mat
def to_matrix(self):
        w, x, y, z = self.normalize().data  # pylint: disable=C0103
        mat = np.array([
            [1-2*y**2-2*z**2, 2*x*y-2*z*w, 2*x*z+2*y*w],
            [2*x*y+2*z*w, 1-2*x**2-2*z**2, 2*y*z-2*x*w],
            [2*x*z-2*y*w, 2*y*z+2*x*w, 1-2*x**2-2*y**2]
        ], dtype=float)
        return mat
def to_matrix ( self ) : w , x , y , z = self . normalize ( ) . data # pylint: disable=C0103 mat = np . array ( [ [ 1 - 2 * y ** 2 - 2 * z ** 2 , 2 * x * y - 2 * z * w , 2 * x * z + 2 * y * w ] , [ 2 * x * y + 2 * z * w , 1 - 2 * x ** 2 - 2 * z ** 2 , 2 * y * z - 2 * x * w ] , [ 2 * x * z - 2 * y * w , 2 * y * z + 2 * x * w , 1 - 2 * x ** 2 - 2 * y ** 2 ] ] , dtype = float ) return mat
Converts a unit-length quaternion to a rotation matrix.

        Returns:
            ndarray: Rotation matrix.
Converts a unit - length quaternion to a rotation matrix .