• kdb+

  xbar millisecond

  Posted by powerpeanuts on September 9, 2022 at 12:00 am

  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?

  powerpeanuts replied 1 month ago 4 Members · 3 Replies
• 3 Replies

• 

  cillianreilly

  Member

  September 9, 2022 at 12:00 am

  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

  Member

  September 9, 2022 at 12:00 am

  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

  Member

  September 11, 2022 at 12:00 am

  5 xbar `time$time

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