如何在 python 中的两个不同 y 轴上绘制两个变量？

Question

我尝试构建一个具有一个 x 轴和两个 y 轴的图形，所有轴都来自数据框（类似于图形 here）。这是我的示例数据：

import pandas as pd

df = pd.DataFrame(data={'year': [2000, 2001, 2002], 
                        'deaths': [327, 456, 509], 
                        'cheese': [13.5, 13.7, 13.8]})

我只找到了涵盖 or more than two axis with an answer I, as a beginner, don't understand.

的问题

Answer 1

matplotlib.pyplot 模块创建图形和坐标轴对象（详见 help(plt.subplots)），可用于按要求创建绘图：

import matplotlib.pyplot as plt # Impot the relevant module

fig, ax = plt.subplots() # Create the figure and axes object

# Plot the first x and y axes:
df.plot(x = 'year', y = 'deaths', ax = ax) 
# Plot the second x and y axes. By secondary_y = True a second y-axis is requested:
# (see https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.plot.html for details)
df.plot(x = 'year', y = 'cheese', ax = ax, secondary_y = True)

输出：

如何在 python 中的两个不同 y 轴上绘制两个变量？

How to plot two variables on two different y-axes in python?

python

plot

axis

matplotlib

pandas