How do you plot a vertical line on a time series plot in Pandas?

Question

• How do you plot a vertical line (vlines) in a Pandas series plot?
• I am using Pandas to plot rolling means, etc., and would like to mark important

Answer 1

DataFrame plot function returns AxesSubplot object and on it, you can add as many lines as you want. Take a look at the code sample below:

%matplotlib inline

import pandas as pd
import numpy as np

df = pd.DataFrame(index=pd.date_range("2019-07-01", "2019-07-31"))  # for sample data only
df["y"] = np.logspace(0, 1, num=len(df))  # for sample data only

ax = df.plot()
# you can add here as many lines as you want
ax.axhline(6, color="red", linestyle="--")
ax.axvline("2019-07-24", color="red", linestyle="--")