python - 单击图例时如何更改 matplot 中一组点的颜色？

Question

当我点击其图例标签时，任何人都可以帮助如何更改 pyplot 中一组点的颜色？

下面是一段代码，其中有两组点 x1 和 x2。我将它们绘制成散点图。它以蓝色绘制集合 x1 和 x2 中的所有点。当我点击图例 x1 标签时，有没有办法将集合 x1 中的点的颜色更改为红色

import matplotlib.pyplot as plot
x1 = [1,3,5,7,9]
x2 = [2,4,6,8,10]
fig, ax = plot.subplots()
ax.scatter(x1,x1,color = 'b',s = 50,label = 'x1')
ax.scatter(x2,x2,color = 'b',s = 50,label = 'x2')
ax.legend(loc = 'upper left')
plot.show()

Answer 1

matplotlib 文档中有一个关于 legend picking 的例子.我们可能会对其进行调整，以适应散点上发生拾取并且颜色要发生变化的情况。

为此，我们在传奇艺术家(代理)上创建了一个选择器并附加了一个属性 toggled to 是要知道艺术家处于两种状态中的哪一种(这比使用 get_color 更容易，因为颜色在内部转换为 RGB 元组)。

import matplotlib.pyplot as plt


x1 = [1,3,5,7,9]
x2 = [2,4,6,8,10]
fig, ax = plt.subplots()
line1 = ax.scatter(x1,x1,color = 'b',s = 50,label = 'x1')
line2 = ax.scatter(x2,x2,color = 'b',s = 50,label = 'x2')
leg = ax.legend(loc = 'upper left')

# we will set up a dict mapping legend line to orig line, and enable
# picking on the legend line
lines = [line1, line2]
lined = dict()
for legline, origline in zip(leg.legendHandles, lines):
    legline.set_picker(5)  # 5 pts tolerance
    legline.toggled = False  # create custom attribute to observe state
    lined[legline] = origline

def onpick(event):
    legline = event.artist
    origline = lined[legline]

    c = "b" if legline.toggled else "r"
    legline.set_color(c)
    origline.set_color(c)

    fig.canvas.draw_idle()

    legline.toggled = not legline.toggled


fig.canvas.mpl_connect('pick_event', onpick)

plt.show()