Extracting year from dataset in python - year appears a decimal point-CodePudding

Trying to extract year from dataset in python

df["YYYY"] = pd.DatetimeIndex(df["Date"]).year

year appears as decimal point in the new column.

YYYY
2001.0
2002.0
2015.0
2022.0

How to just have year appear with no decimal points?

CodePudding user response：

sample program for your problem

import pandas as pd
df = pd.DataFrame({'date': ['3/10/2000', '3/11/2000', '3/12/2000']})
df['date'] = pd.to_datetime(df['date'])
df['year'] = pd.DatetimeIndex(df['date']).year
print(df['year'])

pandas takes care of date by itself

if not we can directly specify as

df["date_feild"] = pd.to_datetime(df["date_feild"])

hope it will make things clear to you.

if not can you specify the df samples

CodePudding user response：

You likely have null values in you input resulting in NaNs and a float type for your column.

No missing values:

pd.DatetimeIndex(['2022-01-01']).year

Int64Index([2022], dtype='int64')

Missing values:

pd.DatetimeIndex(['2022-01-01', '']).year

Float64Index([2022.0, nan], dtype='float64')

I suggest to use pandas.to_datetime combined with convert_dtypes:

pd.to_datetime(pd.Series(['2022-01-01', ''])).dt.year.convert_dtypes()

0    2022
1    <NA>
dtype: Int64

Or to extract directly the year from the initial strings. But for that we would need a sample of the input.