Pandas Series property: dt.is_year_start

Series.dt.is_year_start property

The is_year_start property is used to check whether a given date is the first day of a year or not.

Syntax:

Series.dt.is_year_start

Returns: Series or DatetimeIndex
The same type as the original data with boolean values.
Series will have the same name and index.
DatetimeIndex will have the same name.

Example:

Python-Pandas Code:

import numpy as np
import pandas as pd
dates = pd.Series(pd.date_range("2019-12-30", periods=3))
dates

Output:

0   2019-12-30
1   2019-12-31
2   2020-01-01
dtype: datetime64[ns]

Python-Pandas Code:

import numpy as np
import pandas as pd
dates = pd.Series(pd.date_range("2019-12-30", periods=3))
dates.dt.is_year_start

Output:

0    False
1    False
2     True
dtype: bool

Python-Pandas Code:

import numpy as np
import pandas as pd
idx = pd.date_range("2019-12-30", periods=3)
idx

Output:

DatetimeIndex(['2019-12-30', '2019-12-31', '2020-01-01'], dtype='datetime64[ns]', freq='D')

Python-Pandas Code:

import numpy as np
import pandas as pd
idx = pd.date_range("2019-12-30", periods=3)
idx.is_year_start

Output:

array([False, False,  True])

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