Finding the mean and standard deviation of a timedelta object in pandas df

Question

I would like to calculate the mean and standard deviation of a timedelta by bank from a dataframe with two columns shown

Answer 1

No need to convert timedelta back and forth. Numpy and pandas can seamlessly do it for you with a faster run time. Using your dropped DataFrame:

import numpy as np

grouped = dropped.groupby('bank')['diff']

mean = grouped.apply(lambda x: np.mean(x))
std = grouped.apply(lambda x: np.std(x))