(self, root_rotation)
return heading_rot
Return a quaternion representing the heading rotation of q along the vertical axis (z axis).

    The heading is computing with respect to the robot's default root
    orientation (self._default_root_rotation). This is because different models
    have different coordinate systems, and some models may not have the z axis
    as the up direction.

    Args:
      root_rotation: A quaternion representing the rotation of the robot's root.

    Returns:
      A quaternion representing the rotation about the z axis with respect to
      the default orientation.
Return a quaternion representing the heading rotation of q along the vertical axis (z axis).
Return a quaternion representing the heading rotation of q along the vertical axis ( z axis ) .
def _calc_heading_rot(self, root_rotation):
    """Return a quaternion representing the heading rotation of q along the vertical axis (z axis).

    The heading is computing with respect to the robot's default root
    orientation (self._default_root_rotation). This is because different models
    have different coordinate systems, and some models may not have the z axis
    as the up direction.

    Args:
      root_rotation: A quaternion representing the rotation of the robot's root.

    Returns:
      A quaternion representing the rotation about the z axis with respect to
      the default orientation.

    """
    inv_default_rotation = transformations.quaternion_conjugate(
        self._get_default_root_rotation())
    rel_rotation = transformations.quaternion_multiply(root_rotation,
                                                       inv_default_rotation)
    heading_rot = motion_util.calc_heading_rot(rel_rotation)
    return heading_rot
def _calc_heading_rot ( self , root_rotation ) : inv_default_rotation = transformations . quaternion_conjugate ( self . _get_default_root_rotation ( ) ) rel_rotation = transformations . quaternion_multiply ( root_rotation , inv_default_rotation ) heading_rot = motion_util . calc_heading_rot ( rel_rotation ) return heading_rot