def removeGroundSimple(polyData, groundThickness=0.02, sceneHeightFromGround=0.05):
    ''' Simple ground plane removal algorithm. Uses ground height
        and does simple z distance filtering.
        Suitable for noisy data e.g. kinect/stereo camera
        (Default args should be relaxed, filtering simplfied)
    '''
    groundHeight = SegmentationContext.getGlobalInstance().getGroundHeight()
    origin = [0, 0, groundHeight]
    normal = [0, 0, 1]

    points = vtkNumpy.getNumpyFromVtk(polyData, 'Points')
    dist = np.dot(origin - points, normal)
    vtkNumpy.addNumpyToVtk(polyData, dist, 'dist_to_plane')

    groundPoints = thresholdPoints(polyData, 'dist_to_plane', [-groundThickness/2.0, groundThickness/2.0])
    scenePoints = thresholdPoints(polyData, 'dist_to_plane', [sceneHeightFromGround, 100])

    return groundPoints, scenePoints
dataset/ETHPy150Open RobotLocomotion/director/src/python/director/segmentation.py/removeGroundSimple/swapped operands of `-`