从 plot 图例中删除点

Question

I have this code that shows the Lagrange interpolation between set of points(x,y cordination). Using matplotlib:

import numpy as np
from scipy.interpolate import lagrange
import matplotlib.pyplot as plt

x1 = [0.2, 0.4, 0.6, 0.8]
y1 = [1, 2, 4, 6]
x2 = [0.2, 0.4, 0.6, 0.8]
y2 = [3, 10, 19, 43]
x_new = np.arange(0.2, 0.8, 0.1)
x_new2 = np.arange(0.2, 0.8, 0.1)
f = lagrange(x1, y1)
f2 = lagrange(x2, y2)
fig = plt.figure(figsize=(8, 6))
plt.plot(x_new, f(x_new), 'y', x1, y1, 'ro', label='$r = 20')
plt.plot(x_new2, f2(x_new2), 'b', x2, y2, 'ro', label='$r = 40')
plt.legend(loc='best')
plt.title('Lagrange Polynomial')
plt.grid()
plt.xlabel('r')
plt.ylabel('cut size')
plt.show()

My output:

I want to remove the red points in the legend. How can I do that?

Answer 1

Break markers into new lines

import numpy as np from scipy.interpolate import lagrange import matplotlib.pyplot as plt

x1 = [0.2, 0.4, 0.6, 0.8]
y1 = [1, 2, 4, 6]
x2 = [0.2, 0.4, 0.6, 0.8]
y2 = [3, 10, 19, 43]
x_new = np.arange(0.2, 0.8, 0.1)
x_new2 = np.arange(0.2, 0.8, 0.1)
f = lagrange(x1, y1)
f2 = lagrange(x2, y2)
fig = plt.figure(figsize=(8, 6))
plt.plot(x_new, f(x_new), 'y',  label='$r = 20')
plt.plot(x1, y1, 'ro')
plt.plot(x_new2, f2(x_new2), 'b', label='$r = 40')
plt.plot( x2, y2, 'ro')
plt.legend(loc='best')
plt.title('Lagrange Polynomial')
plt.grid()
plt.xlabel('r')
plt.ylabel('cut size')
plt.show()

which now gives