from datetime import date
import pandas as pd
from woodwork.column_schema import ColumnSchema
from woodwork.logical_types import Categorical, Datetime
from featuretools.primitives.base import TransformPrimitive
[docs]class Season(TransformPrimitive):
    """Determines the season of a given datetime.
        Returns winter, spring, summer, or fall.
        This only works for northern hemisphere.
    Description:
        Given a list of datetimes, return the season of each one
        (`winter`, `spring`, `summer`, or `fall`).
    Examples:
        >>> from datetime import datetime
        >>> times = [datetime(2019, 1, 1),
        ...          datetime(2019, 4, 15),
        ...          datetime(2019, 7, 20),
        ...          datetime(2019, 12, 30)]
        >>> season = Season()
        >>> season(times).tolist()
        ['winter', 'spring', 'summer', 'winter']
    """
    name = "season"
    input_types = [ColumnSchema(logical_type=Datetime)]
    return_type = ColumnSchema(logical_type=Categorical, semantic_tags={"category"})
    def get_function(self):
        def season(x):
            # https://stackoverflow.com/a/28688724/2512385
            Y = 2000  # dummy leap year to allow input X-02-29 (leap day)
            seasons = [
                ("winter", (date(Y, 1, 1), date(Y, 3, 20))),
                ("spring", (date(Y, 3, 21), date(Y, 6, 20))),
                ("summer", (date(Y, 6, 21), date(Y, 9, 22))),
                ("fall", (date(Y, 9, 23), date(Y, 12, 20))),
                ("winter", (date(Y, 12, 21), date(Y, 12, 31))),
            ]
            x = x.apply(lambda x: x.replace(year=2000))
            def get_season(dt):
                for season, (start, end) in seasons:
                    if not pd.isna(dt) and start <= dt.date() <= end:
                        return season
                return pd.NA
            new = x.apply(get_season).astype(dtype="string")
            return new
        return season