Dataframe resample

https://www.cnblogs.com/hhh5460/p/5596340.html

附：常见时间频率
A year
M month
W week
D day
H hour
T minute
S second

def custom_resampler(array_like):
    return np.sum(array_like)+5

series.resample('3T').apply(custom_resampler)