How to calculate time difference between two pandas column [duplicate]

问题

My df looks like,

    start               stop
0   2015-11-04 10:12:00 2015-11-06 06:38:00
1   2015-11-04 10:23:00 2015-11-05 08:30:00
2   2015-11-04 14:01:00 2015-11-17 10:34:00
4   2015-11-19 01:43:00 2015-12-21 09:04:00

print(time_df.dtypes)

start       datetime64[ns]
stop        datetime64[ns]

dtype: object

I am trying to find the time difference between, stop and start.

I tried, pd.Timedelta(df_time['stop']-df_time['start']) but it gives TypeError: data type "datetime" not understood

df_time['stop']-df_time['start'] also gives same error.

My expected output,

 2D,?H
 1D,?H
 ...
 ...

回答1:

You need omit pd.Timedelta, because difference of times return timedeltas:

df_time['td'] = df_time['stop']-df_time['start']
print (df_time)
                start                stop               td
0 2015-11-04 10:12:00 2015-11-06 06:38:00  1 days 20:26:00
1 2015-11-04 10:23:00 2015-11-05 08:30:00  0 days 22:07:00
2 2015-11-04 14:01:00 2015-11-17 10:34:00 12 days 20:33:00

EDIT: Another solution is subtract numpy arrays:

df_time['td'] = df_time['stop'].values - df_time['start'].values
print (df_time)
                start                stop               td
0 2015-11-04 10:12:00 2015-11-06 06:38:00  1 days 20:26:00
1 2015-11-04 10:23:00 2015-11-05 08:30:00  0 days 22:07:00
2 2015-11-04 14:01:00 2015-11-17 10:34:00 12 days 20:33:00

回答2:

First make sure that you have dates in your column

data.loc[:, 'start'] = pd.to_datetime(data.loc[:, 'start'])
data.loc[:, 'stop'] = pd.to_datetime(data.loc[:, 'stop'])

Then substract

data['delta'] = data['stop'] - data['start']

来源：https://stackoverflow.com/questions/51381290/how-to-calculate-time-difference-between-two-pandas-column

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python

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data-analysis