import pandas as pd data_range = pd.date_range(start='2010-10-01', end='2010-10-31') df = pd.Dataframe(data=data_range, columns=['day']) df['day_of_year'] = df['day'].dt.dayofyear print(df)
打印结果：
day day_of_year 0 2010-10-01 274 1 2010-10-02 275 2 2010-10-03 276 3 2010-10-04 277 4 2010-10-05 278 5 2010-10-06 279 6 2010-10-07 280 7 2010-10-08 281 8 2010-10-09 282 9 2010-10-10 283 10 2010-10-11 284 11 2010-10-12 285 12 2010-10-13 286 13 2010-10-14 287 14 2010-10-15 288 15 2010-10-16 289 16 2010-10-17 290 17 2010-10-18 291 18 2010-10-19 292 19 2010-10-20 293 20 2010-10-21 294 21 2010-10-22 295 22 2010-10-23 296 23 2010-10-24 297 24 2010-10-25 298 25 2010-10-26 299 26 2010-10-27 300 27 2010-10-28 301 28 2010-10-29 302 29 2010-10-30 303 30 2010-10-31 304
