_pick_info.py 文件源码

def _(artist, event):
    if type(artist) != AxesImage:
        # Skip and warn on subclasses (`NonUniformImage`, `PcolorImage`) as
        # they do not implement `contains` correctly.  Even if they did, they
        # would not support moving as we do not know where a given index maps
        # back physically.
        return compute_pick.dispatch(object)(artist, event)
    contains, _ = artist.contains(event)
    if not contains:
        return
    ns = np.asarray(artist.get_array().shape)[::-1]  # (y, x) -> (x, y)
    xy = np.array([event.xdata, event.ydata])
    xmin, xmax, ymin, ymax = artist.get_extent()
    # Handling of "upper" origin copied from AxesImage.get_cursor_data.
    if artist.origin == "upper":
        ymin, ymax = ymax, ymin
    low, high = np.array([[xmin, ymin], [xmax, ymax]])
    idxs = ((xy - low) / (high - low) * ns).astype(int)[::-1]
    target = with_attrs(xy, index=tuple(idxs))
    return Selection(artist, target, 0, None, None)