Python 在直方图顶部添加拟合线

我正在绘制指数分布的柱状图，如下所示。如何在直方图顶部添加拟合线

from scipy.stats import expon
import matplotlib.pyplot as plt
data_expon = expon.rvs(size=1000,scale=1,loc=0)
# the histogram of the data
plt.hist(data_expon, 100, density=True, facecolor='r', alpha=0.75)
plt.xlabel('exponential')
plt.ylabel('PDF')

plt.grid(True)
plt.show()

也可以读取可能的副本您也可以尝试

import matplotlib.pyplot as plt
import numpy as np


random_state = np.random.RandomState(19680801)
X = random_state.randn(10000)

fig, ax = plt.subplots()
ax.hist(X, bins=25, density=True)
x = np.linspace(-5, 5, 1000)
ax.plot(x, 1 / np.sqrt(2*np.pi) * np.exp(-(x**2)/2), linewidth=4)
ax.set_xticks([])
ax.set_yticks([])
fig.savefig("histogram_frontpage.png", dpi=25)  # results in 160x120 px image