如何在matplotlib中首先绘制线条并指向最后一点

Question

I have a simple plot with several sets of points and lines connecting each set. I want the points to be plotted on top of the lines (so that the line doesn't show inside the point). Regardless of order of the plot and scatter calls, this plot comes out the same, and not as I'd like. Is there a simple way to do it?

import math
import matplotlib.pyplot as plt

def poisson(m):
    def f(k):
        e = math.e**(-m)
        f = math.factorial(k)
        g = m**k
        return g*e/f
    return f

R = range(20)
L = list()
means = (1,4,10)
for m in means:
    f = poisson(m)
    L.append([f(k) for k in R])
colors = ['r','b','purple']

for c,P in zip(colors,L):
    plt.plot(R,P,color='0.2',lw=1.5)
    plt.scatter(R,P,s=150,color=c)

ax = plt.axes()
ax.set_xlim(-0.5,20)
ax.set_ylim(-0.01,0.4)
plt.savefig('example.png')

Answer 1

You need to set the Z-order.

plt.plot(R,P,color='0.2',lw=1.5, zorder=1)
plt.scatter(R,P,s=150,color=c, zorder=2)

Check out this example. http://matplotlib.sourceforge.net/examples/pylab_examples/zorder_demo.html