How do I get cumulative moving average?

[brdennehy]

Hi guys,

I am trying to compute and chart the cumulative moving average (ref. of what is it:https://en.wikipedia.org/wiki/Moving_average#Cumulative_moving_average)

The point is that I am doing the following query:

host=SARITA source="login.csv" | reverse | accum elapsed_time as cumulative_elapsed_time | timechart span=5h last(cumulative_elapsed_time) by server

And what I get from it is the cumulative sum. Now what I still need is to get cumulative count (which means, for any "n" value, to get the amount n up to that point in time, but not the total amount of values of all that series), so I can divide the cumulative value by the cumulative count, thus having the cumulative average.

Please help me with this, as I am really stuck on it. Thank you very much in advance for your patience.

Best regards,
Brian

[richgalloway · Accepted solution]

Use the streamstats command to count the events.

host=SARITA source="login.csv" 
| reverse 
| streamstats count 
| accum elapsed_time as cumulative_elapsed_time 
| timechart span=5h last(cumulative_elapsed_time) by server

Even better would be to let streamstats do the moving average for you.

host=SARITA source="login.csv" 
| reverse 
| streamstats time_window=5h avg(elapsed_time) as AvgElapsedTime by server

[brdennehy]

Thanks!! I'll try the streamstats tomorrow.

The problem with your suggestion of making streamstats to do the moving average for me is that the time window must be from the first measure until that point n in question, and not 5h....

[richgalloway]

I chose the time_window option based on your use of timechart span=5h, but you can use another option that works better for your use case.

[brdennehy]

Thanks man! I used the default (non specified) time-frame. I read that the limit is 10,000 events, but it's ok. I only have 2 events per day.

Thank you very much!!!