def min_max_normalize(img):
    """Centre and normalize a given array.

    Parameters:
    ----------
    img: np.ndarray

    """

    min_img = img.min()
    max_img = img.max()

    return (img - min_img) / (max_img - min_img)
Centre and normalize a given array.

    Parameters:
    ----------
    img: np.ndarray