Question

Say that you have a sorted list of n timestamps (Python datetime objects). How would you yield a list of tuples of the form (t, count), where t is a datetime object and count is the number of elements in the list at most x minutes from t?

For example, given the dates (strings, for brevity; in reality datetime objects):

timestamps = ["13:00", "13:01", "13:03", "13:04", "13:05", "13:06", "13:09"]

if x is two minutes, then yield

[("13:00", 2), ("13:03":3), ("13:06":1), ("13:09", 1)]]

What I’m trying to do is make a coarser list of hits on a resource, and the only data I have is the access time of every hit (the granularization is to the millisecond, and I’d like it granular to the minute, or ten minutes)

I would post my attempts, but I’m ashamed…

Edit: This is what I have so far… testing to see if it works…

def group_timestamps(timestamps, chunksize=10):
    """Groups a list of timestamps in chunks of ``chunksize`` minutes"""
    cs = timedelta(minutes=chunksize)

    if not timestamps:
        return []

    t0 = timestamps[0]
    count = 1
    chunks = []

    for ts in timestamps:
        if (ts - t0) <= cs:
            count += 1
        else:
            chunks.append((t0, count))
            t0 = ts
            count = 1
    return chunks

Answer 1

This should work:

current = timestamps[0]
count = 0
res = []
for t in timestamps:
    if (t - current) <=  timedelta(minutes= 2): 
         count = count + 1
    else:
         res.append((current,count))
         current = t
         count = 1
res.append(current,count) #add last tuple

Following your example:

timestamps = [datetime(hours=13,minutes=00), datetime(hours=13,minutes=01), datetime(hours=13,minutes=03), datetime(hours=13,minutes=04), datetime(hours=13,minutes=05), datetime(hours=13,minutes=06), datetime(hours=13,minutes=09)]

res = [(datetime(hours=13,minutes=00),2),(datetime(hours=13,minutes=03),3),(datetime(hours=13,minutes=06),1),(datetime(hours=13,minutes=09),1)]