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Adding a new column to a dataframe
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Adding a new column to a dataframe
#2
import pandas as pd
 
url='https://raw.githubusercontent.com/nytimes/covid-19-data/master/us-states.csv'
data = pd.read_csv(url, parse_dates=['date'])
data['DOW'] = data['date'].apply(lambda x: x.strftime('%A'))

# if you don't want to convert date columne:
# data = pd.read_csv(url)
# data['DOW'] = pd.to_datetime(data['date']).apply(lambda x: x.strftime('%A'))

print(data.head())
Output:
date state fips cases deaths DOW 0 2020-01-21 Washington 53 1 0 Tuesday 1 2020-01-22 Washington 53 1 0 Wednesday 2 2020-01-23 Washington 53 1 0 Thursday 3 2020-01-24 Illinois 17 1 0 Friday 4 2020-01-24 Washington 53 1 0 Friday
In the example I convert date column to datetime object when I read the csv file. In the comments - example if you do not want to convert it
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Messages In This Thread
Adding a new column to a dataframe - by lokhtar - Jan-14-2021, 03:45 PM
RE: Adding a new column to a dataframe - by buran - Jan-14-2021, 03:57 PM
RE: Adding a new column to a dataframe - by buran - Jan-14-2021, 07:18 PM

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