TypeError using timedelta, cannot sum times

杀马特。学长 韩版系。学妹 提交于 2021-02-11 04:56:14

问题


I have data that looks like this:

    user                in               out location  flag     Time
0    ron  12/21/2021 10:11  12/21/2016 17:50     home     0  4:19:03
1    ron  12/21/2016 13:26  12/21/2016 13:52   office     2  0:25:28
2  april   12/21/2016 8:12  12/21/2016 17:27   office     0  8:15:03
3  april  12/21/2016 18:54  12/21/2016 22:56   office     0  4:02:36
4   andy   12/21/2016 8:57  12/21/2016 12:15     home     0  2:59:40

I want to sum or take the max value of time per user based on the flag. So I converted the column to timedelta.

sample.loc[:,'Time'] = pd.to_timedelta(sample['Time'])

However, when I try to test this by summing the entire column

sum(sample['Time'])

I get the following error:

TypeError: unsupported operand type(s) for +: 'int' and 'Timedelta'

What am I missing here? I thought you could sum with Timedelta.


回答1:


Python's sum, by default, assumes you are summing integers. Hence it tries to start summing from 0, which is where this error comes from. It's impossible to add 0 to a timedelta.

This can be fixed in 2 ways:

  • Provide a different starting value to sum, perhaps an "empty" timedelta, as the second argument for sum:

    from datetime import timedelta
    ...
    sum(sample['Time'], timedelta())
    
  • Use Series.sum (which will probably have better performance anyway):

    sample['Time'].sum()
    



回答2:


In order to take the sum of the number of days that you received using pd.to_timedelta(), you need to do the following:

sum(sample.Time.astype('int'))/8.64e+13

That is, you need to convert the 'Time' column integer to perform the sum() operation. 8.64e+13 is to convert the ns to days.



来源:https://stackoverflow.com/questions/60804162/typeerror-using-timedelta-cannot-sum-times

易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!