我有以下数据框:
Time Work
2018-12-01 10:00:00 Off
2018-12-01 10:00:02 On
2018-12-01 10:00:05 On
2018-12-01 10:00:06 On
2018-12-01 10:00:07 On
2018-12-01 10:00:09 Off
2018-12-01 10:00:11 Off
2018-12-01 10:00:14 On
2018-12-01 10:00:16 On
2018-12-01 10:00:18 On
2018-12-01 10:00:20 Off
我想创建一个新列,其中包含设备开始工作以来耗时。
Time Work Elapsed Time
2018-12-01 10:00:00 Off 0
2018-12-01 10:00:02 On 2
2018-12-01 10:00:05 On 5
2018-12-01 10:00:06 On 6
2018-12-01 10:00:07 On 7
2018-12-01 10:00:09 Off 0
2018-12-01 10:00:11 Off 0
2018-12-01 10:00:14 On 3
2018-12-01 10:00:16 On 5
2018-12-01 10:00:18 On 7
2018-12-01 10:00:20 Off 0
我该怎么做?
最佳答案
你可以使用groupby
:
# df['Time'] = pd.to_datetime(df['Time'], errors='coerce') # Uncomment if needed.
sec = df['Time'].dt.second
df['Elapsed Time'] = (
sec - sec.groupby(df.Work.eq('Off').cumsum()).transform('first'))
df
Time Work Elapsed Time
0 2018-12-01 10:00:00 Off 0
1 2018-12-01 10:00:02 On 2
2 2018-12-01 10:00:05 On 5
3 2018-12-01 10:00:06 On 6
4 2018-12-01 10:00:07 On 7
5 2018-12-01 10:00:09 Off 0
6 2018-12-01 10:00:11 Off 0
7 2018-12-01 10:00:14 On 3
8 2018-12-01 10:00:16 On 5
9 2018-12-01 10:00:18 On 7
10 2018-12-01 10:00:20 Off 0
这个想法是提取秒部分并从状态从“关闭”变为“开启”的第一刻减去耗时。这是使用 transform
和 first
完成的。
cumsum
用于标识组:
df.Work.eq('Off').cumsum()
0 1
1 1
2 1
3 1
4 1
5 2
6 3
7 3
8 3
9 3
10 4
Name: Work, dtype: int64
如果您的设备有可能在“开启”状态下持续数分钟,则将 sec
初始化为:
sec = df['Time'].values.astype(np.int64) // 10e8
df['Elapsed Time'] = (
sec - sec.groupby(df.Work.eq('Off').cumsum()).transform('first'))
df
Time Work Elapsed Time
0 2018-12-01 10:00:00 Off 0.0
1 2018-12-01 10:00:02 On 2.0
2 2018-12-01 10:00:05 On 5.0
3 2018-12-01 10:00:06 On 6.0
4 2018-12-01 10:00:07 On 7.0
5 2018-12-01 10:00:09 Off 0.0
6 2018-12-01 10:00:11 Off 0.0
7 2018-12-01 10:00:14 On 3.0
8 2018-12-01 10:00:16 On 5.0
9 2018-12-01 10:00:18 On 7.0
10 2018-12-01 10:00:20 Off 0.0
关于python - Pandas 测量自条件以来耗时,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/53656878/