xbar millisecond

[powerpeanuts]

Hi,

in the select statement, we can easily do 5 xbar time.minute to group the data for every 5 minutes, what is the equivalent for doing like every 5 millisecond?

[cillianreilly]

If you don't cast to minutes first, you can explicitly group by millisecond (assuming your time column is a timestamp):

q)t:([]time:.z.p+500000*til 20;col:til 20)
q)select avg col by 5000000 xbar time from t    // millisecond = 1000000 nanoseconds
time                         | col
-----------------------------| ----
2022.09.09D03:50:38.425000000| 2.5
2022.09.09D03:50:38.430000000| 10.5
2022.09.09D03:50:38.435000000| 17.5

[rocuinneagain]

A timespan can be used directly 

q)select avg col by 0D00:00:00.005 xbar time from t
time                         | col
-----------------------------| ----
2022.09.09D07:40:23.110000000| 3
2022.09.09D07:40:23.115000000| 11.5
2022.09.09D07:40:23.120000000| 18

[sujoy]

5 xbar `time$time