纪元时间格式到python datetime

Question

I am reading data from csv file with pandas. The time column is in epoch format which needs to be converted to human readable datetime. The dataframe looks like this:

name    time    rCurrentL1  rCurrentL2  rCurrentL3
0   Assembler_No1BC1_ElecData   1623691319004000000 0.0032874299213290215   0.0021221311762928963   0.00042045069858431816
1   Assembler_No1BC1_ElecData   1623691319005000000 0.0032874299213290215   0.0021221311762928963   0.00042045069858431816
2   Assembler_No1BC1_ElecData   1623691319006000000 0.0032874299213290215   0.0021221311762928963   0.00042045069858431816

I tried pd.to_datetime(df['time'], unit='ns') but get OverflowError: Python int too large to convert to C long . Could anyone help me how to fix this? Or is there a better way to convert epoch to datetime?

Answer 1

As @Corralien comment, some rows didn't have numeric values and could not be converted. I checked them with df[pd.to_numeric(df['time'], errors='coerce').isna()] and excluded them from DataFrame. Then df['time'] = pd.to_datetime(df['time'], unit='ns') worked fine.

Answer 2

    Epoch
1   1609459009.0
2   1609458998.0
3   1609458963.0
4   1609458893.0
5   1609458770.0
6   1609458685.0
7   1609458551.0
8   1609458465.0
9   1609458432.0
10  1609458369.0

I tried df['time'] = pd.to_datetime(df['time'], unit='ns') but it doesnt work. Keeps saying KeyError: 'time' I am trying to convert the epoch date column to python datetime but it doesnt seem to work. I am reading the file as a csv and trying to convert the times.