查找DataFrame中的两个日期周期之间是否有重叠

Question

我有以下pd.DataFrame

df = pd.DataFrame({'admission_timestamp': ['2021-01-17 17:45:00', '2020-03-31 23:32:00', '2020-03-27 18:20:00', '2020-04-17 18:12:00', '2020-03-19 19:12:00'], 'end_period': ['2021-01-18 17:45:00', '2020-04-01 23:32:00', '2020-03-28 18:20:00', '2020-04-18 18:12:00', '2020-03-20 19:12:00'], 'start_med': ['NaT', '2020-04-01 00:00:00', '2020-03-27 19:00:00', '2020-04-17 18:39:24', 'NaT'], 'end_med': ['NaT', '2020-04-14 21:00:00', '2020-04-05 00:00:00', '2020-05-06 22:07:29', 'NaT']})

看起来像：

admission_timestamp  end_period           start_med            end_med 
1  2021-01-17 17:45:00  2021-01-18 17:45:00  NaT                  NaT   
2  2020-03-31 23:32:00  2020-04-01 23:32:00  2020-04-01 00:00:00  2020-04-14 21:00:00
3  2020-03-27 18:20:00  2020-03-28 18:20:00  2020-03-27 19:00:00  2020-04-05 00:00:00
4  2020-04-17 18:12:00  2020-04-18 18:12:00  2020-04-17 18:39:24  2020-05-06 22:07:29   
5  2020-03-19 19:12:00  2020-03-20 19:12:00  NaT                  NaT

我想创建一个新的列received_medidation，说明患者是否在admission_timestamp和end_period之间接受了药物治疗(布尔值((即使只有一秒钟(。因此，布尔值应该说明admission_timestamp和end_period之间是否有任何时间与start_med和end_med之间的时间重叠。数据类型都是日期时间64[ns]。

我知道我们可以创建诸如之类的布尔掩码

condition = (df['date'] > start_date) & (df['date'] <= end_date)

然而，我不明白这怎么可能解决上述任务。感谢您的帮助。

Answer 1

如果保证start_med晚于admission_timestamp，则start_med日期在admission_timestamp和end_period之间就足够了

for col in df.columns:
df[col] = pd.to_datetime(df[col])
df['received_medidation'] = (df['admission_timestamp'] < df['start_med']) & (df['start_med'] < df['end_period'])

然而，如果start_med可以在admission_timestamp之前，那么这意味着'start_med' < 'admission_timestamp' < 'end_med'也会创建日期的交集。然后，我们将此情况与使用OR运算符的上一个情况包括在内：

df['received_medidation'] = (df['start_med'].between(df['admission_timestamp'], df['end_period']) |
df['admission_timestamp'].between(df['start_med'], df['end_med']))

注意：这里的总体假设是admission_timestamp < end_period和start_med < end_med总是正确的，在这种情况下，上面的逻辑表达式捕获所有相交的日期。

输出：

admission_timestamp          end_period           start_med  
0 2021-01-17 17:45:00 2021-01-18 17:45:00                 NaT   
1 2020-03-31 23:32:00 2020-04-01 23:32:00 2020-04-01 00:00:00   
2 2020-03-27 18:20:00 2020-03-28 18:20:00 2020-03-27 19:00:00   
3 2020-04-17 18:12:00 2020-04-18 18:12:00 2020-04-17 18:39:24   
4 2020-03-19 19:12:00 2020-03-20 19:12:00                 NaT   
end_med  received_medidation  
0                 NaT                False  
1 2020-04-14 21:00:00                 True  
2 2020-04-05 00:00:00                 True  
3 2020-05-06 22:07:29                 True  
4                 NaT                False  

Answer 2

使用between

df['overlaps'] = df['start_med'].between(df['admission_timestamp'], df['end_period']) 
| df['end_med'].between(df['admission_timestamp'], df['end_period'])
print(df)
# Output
admission_timestamp          end_period           start_med             end_med  overlaps
1 2021-01-17 17:45:00 2021-01-18 17:45:00                 NaT                 NaT     False
2 2020-03-31 23:32:00 2020-04-01 23:32:00 2020-04-01 00:00:00 2020-04-14 21:00:00      True
3 2020-03-27 18:20:00 2020-03-28 18:20:00 2020-03-27 19:00:00 2020-04-05 00:00:00      True
4 2020-04-17 18:12:00 2020-04-18 18:12:00 2020-04-17 18:39:24 2020-05-06 22:07:29      True
5 2020-03-19 19:12:00 2020-03-20 19:12:00                 NaT                 NaT     False