请看以下代码：
class PickCursor(object):
def __init__(self, collection, alpha_other=0.3, tolerance=5):
self.collection = collection
self.alpha_other = alpha_other
self.pts= collection.get_offsets()
self.num_pts = len(self.pts)
# Need to set a tolerance to make it take effect
self.collection.set_picker(tolerance)
# Ensure that we have separate colors for each object
self.fc = collection.get_facecolors()
if len(self.fc) == 0:
raise ValueError('Collection must have a facecolor')
elif len(self.fc) == 1:
self.fc = np.tile(self.fc, (self.num_pts, 1))
# self.fc is a 2d array every row follows [r, g, b, a]
self.ind = None
self.point_selected = None
self.canvas = ax.figure.canvas
self.canvas.mpl_connect('pick_event', self.onselect)
def onselect(self, event):
self.ind = event.ind[0]
self.point_selected = self.pts[self.ind]
# Change alpha of other points
self.fc[:, -1] = self.alpha_other
self.fc[self.ind, -1] = 1
self.collection.set_facecolors(self.fc)
self.canvas.draw_idle()
fig, ax = plt.subplots(1, 1, figsize=(8, 8))
x = np.arange(0, 10)
y = np.arange(0, 10)
scat = ax.scatter(x, y, s=15)
PickCursor(scat)
上面的代码有效！基本上，它将使未选择的点透明。但是，如果我将代码包装成这样的函数：
def func():
fig, ax = plt.subplots(1, 1, figsize=(8, 8))
x = np.arange(0, 10)
y = np.arange(0, 10)
scat = ax.scatter(x, y, s=15)
PickCursor(scat)
func() ## this line does not work!!!
有人请对此有所了解吗？谢谢！