movies

| Movies | Release Date |
| -------- | -------------- |
| Star Wars: Episode VII - The Force Awakens (2015) | December 16, 2015            |
| Avengers: Endgame (2019   | April 24, 2019               |

I am trying to have a new column and use split to have the year.

import pandas as pd
df = pd.DataFrame({'Movies': ['Star Wars: Episode VII - The Force Awakens (2015)', 'Avengers: Endgame (2019'], 
                   'Release Date': ['December 16, 2015', 'April 24, 2019' ]})    
movies["year"]=0
movies["year"]= movies["Release Date"].str.split(",")[1]
movies["year"]

TO BE

| Movies | year |
| -------- | -------------- |
| Star Wars: Episode VII - The Force Awakens (2015) | 2015            |
| Avengers: Endgame (2019)   | 2019            |

BUT

> ValueError: Length of values does not match length of index 

CodePudding user response：

Using str.extract we can target the 4 digit year:

df["year"] = df["Release Date"].str.extract(r'\b(\d{4})\b')

CodePudding user response：

Explanation

1. movies["Release Date"].str.split(",") returns a series of of the lists returns by split()

2. movies["Release Date"].str.split(",")[1] return the second element of this series.

   This is obviouly not what you want.

Solutions

• Keep using pandas.str.split. but then a function that gets the 2nd item of the series rows for example:

  movies["Release Date"].str.split(",").map(lambda x: x[1])

• Do something different as suggestted by @Tim Bielgeleisen