Working with dates in pandas

[Scott]

Sorry one more quick question, can I do this or is it bad practice:

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import pandas as pd from io import StringIO    data = StringIO( """OBJECTID,Start Date 1,2018-01-11 12:00:00 2,2018-11-01 12:00:00 3,2019-04-11 12:00:00 4,2021-11-03 12:00:00""") df = pd.read_csv(data, parse_dates=["Start Date"], index_col="OBJECTID") df["Start Date"] = df["Start Date"].dt.date print(df)

[Pedroski55]

There is no punishment for playing around in Python!

1	df["Start_Date"] = df["Start Date"].dt.date

Output:
df
                  Start Date  Start_Date
OBJECTID                                
1        2018-01-11 12:00:00  2018-01-11
2        2018-11-01 12:00:00  2018-11-01
3        2019-04-11 12:00:00  2019-04-11
4        2021-11-03 12:00:00  2021-11-03

[deanhystad]

Replacing columns in a dataframe is an accepted programming practice.

Output:
df["Start Date"].dt.date

creates a new series.

df["Start_Date"] = df["Start Date"].dt.date

adds this series to df, replacing the old series.

[snippsat]

Sorry one more quick question, can I do this or is it bad practice:

Use dt.normalize() then you don't mess up types,which should be datetime64[ns].
Remember the first thing to always with a dataframe is to check dtypes.

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import pandas as pd from io import StringIO   data = StringIO( """OBJECTID,Start Date 1,2018-01-11 12:00:00 2,2018-11-01 12:00:00 3,2019-04-11 12:00:00 4,2021-11-03 12:00:00""")   df = pd.read_csv(data, parse_dates=["Start Date"], index_col="OBJECTID") df["Start Date"] = df["Start Date"].dt.normalize() #df["Start Date"] = df["Start Date"].dt.date print(df) print(df.dtypes) print('-' * 25) print(df.info())

Output:
         Start Date
OBJECTID           
1        2018-01-11
2        2018-11-01
3        2019-04-11
4        2021-11-03
Start Date    datetime64[ns]
dtype: object
-------------------------
<class 'pandas.core.frame.DataFrame'>
Index: 4 entries, 1 to 4
Data columns (total 1 columns):
 #   Column      Non-Null Count  Dtype         
---  ------      --------------  -----         
 0   Start Date  4 non-null      datetime64[ns]
dtypes: datetime64[ns](1)
memory usage: 64.0 bytes
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