def lm_centres_correction(centres):
    r"""
    Construct a transform that will correct landmarks for a window
    iterating feature calculation

    Parameters
    ----------
    centres : `ndarray` (H, W, 2)
        The location of the window centres in the features

    Returns
    -------
    :map:`Affine`
        An affine transform that performs the correction.
        Should be applied to the landmarks on the target image.
    """
    t = Translation(-centres.min(axis=0).min(axis=0), skip_checks=True)
    step_v = centres[0, 0, 0]
    if centres.shape[0] > 1:
        step_v = centres[1, 0, 0] - centres[0, 0, 0]
    step_h = centres[0, 0, 1]
    if centres.shape[1] > 1:
        step_h = centres[0, 0, 1] - centres[0, 1, 1]
    s = NonUniformScale((1./step_v, 1./step_h), skip_checks=True)
    return t.compose_before(s)
dataset/ETHPy150Open menpo/menpo/menpo/feature/base.py/lm_centres_correction/swapped operands of `-`