python - 인접한 행의 차이로 팬더 데이터 프레임 필터링

boolean indexing 가 필요한 것 같습니다   diff 와 함께  차이점과 1 hour Timedelta 와 비교 :

dates=['2005-07-15 17:00:00','2005-07-17 18:00:00', '2005-07-17 19:00:00',  
      '2005-07-17 23:00:00', '2005-07-18 00:00:00']
df = pd.DataFrame({'a':range(5)}, index=pd.to_datetime(dates))
print (df)
                     a
2005-07-15 17:00:00  0
2005-07-17 18:00:00  1
2005-07-17 19:00:00  2
2005-07-17 23:00:00  3
2005-07-18 00:00:00  4

diff = df.index.to_series().diff().fillna(0)
print (diff)
2005-07-15 17:00:00   0 days 00:00:00
2005-07-17 18:00:00   2 days 01:00:00
2005-07-17 19:00:00   0 days 01:00:00
2005-07-17 23:00:00   0 days 04:00:00
2005-07-18 00:00:00   0 days 01:00:00
dtype: timedelta64[ns]
mask = diff <= pd.Timedelta(1, unit='h')
print (mask)
2005-07-15 17:00:00     True
2005-07-17 18:00:00    False
2005-07-17 19:00:00     True
2005-07-17 23:00:00    False
2005-07-18 00:00:00     True
dtype: bool
df = df[mask]
print (df)
                     a
2005-07-15 17:00:00  0
2005-07-17 19:00:00  2
2005-07-18 00:00:00  4