Generating random dates within a given range in pandas

Question

This is a self-answered post. A common problem is to randomly generate dates between a given start and end date.

There are two cases to consider:

1. random dates with a time component, and
2. random dates without time

For example, given some start date 2015-01-01 and an end date 2018-01-01, how can I sample N random dates between this range using pandas?

Answer 1

We can speed up @akilat90's approach about twofold (in @coldspeed's benchmark) by using the fact that datetime64 is just a rebranded int64 hence we can view-cast:

def pp(start, end, n):
    start_u = start.value//10**9
    end_u = end.value//10**9

    return pd.DatetimeIndex((10**9*np.random.randint(start_u, end_u, n, dtype=np.int64)).view('M8[ns]'))