【Python】绘制双Y轴折线与散点图

import matplotlib.pyplot as plt
import pandas as pd
fig, ax1 = plt.subplots()
df = pd.read_csv('./train_loss.csv')
df_fde = pd.read_csv('./best_fde.csv')
step = df["Step"].values
train_loss = df["Value"].values

step2 = df_fde["Step"].values
best_ade = df_fde["Value"].values
# plt.rcParams["font.sans-serif"]=["SimHei"] #设置字体
# plt.rcParams["axes.unicode_minus"]=False #该语句解决图像中的“-”负号的乱码问题
color = 'tab:red'
ax1.set_xlabel('epoch')
ax1.set_ylabel('Trian Loss', color=color,  fontdict={
    
    'size': 12})
ax1.tick_params(axis='y', labelcolor=color)
a = ax1.plot(step, train_loss, c='red', label="train_loss")
ax2 = ax1.twinx()  # 创建共用x轴的第二个y轴

color = 'tab:blue'
ax2.set_ylabel('Best Fde', color=color,  fontdict={
    
    'size': 12})
b = ax2.plot(step2, best_ade, color=color, label="best_fde", linestyle="--")
ax2.tick_params(axis='y', labelcolor=color)

plt.scatter(step, train_loss, c='red', s = 5)
plt.scatter(step2, best_ade, c='blue', s = 5, marker = "s")

c = a + b
labs = [l.get_label() for l in c]
ax1.legend(c, labs, loc=0,fontsize=12)

# plt.yticks(range(0, 50, 5))
plt.grid(True, linestyle='--', alpha=0.5)
plt.xlabel("epoch", fontdict={
    
    'size': 16})
#plt.title("模型训练数据", fontdict={'size': 20})
plt.show()