Splunk Search

## Problems using delta function

Builder

I'm trying to get the delta between records on a particular field, but when I add the delta function to my search it comes back with results but the new delta field is not created. I suspect it has to do with my source field. It's an energy reading (ex. 1000 kWH). I've used the trim function to cut off the kWH and just leave the number, but it's not working. I tried to use delta on another field and it works fine. Also, when I do pick a field that shows the delta, it's always a negative value, since my field is a counter like an odometer, shouldn't it be a positive value?

sourcetype="Energy_Meter" | eval TE=rtrim(Total_Energy, "kWH") | delta TE p=5 AS delta

Tags (2)
1 Solution
Ultra Champion

Could this be related to the fact that events come back newest-first? If you have a reading from your power meter, it tends to increase over time, and thus the delta would be negative.

``````day    meter    delta
4      123
3      111      -12
2      107      -4
1      101      -6
etc etc
``````

Try reversing search results with `reverse` in that case.

EDIT: had days in the wrong order.... fixed it.

Hope this helps,

Kristian

Ultra Champion

Could this be related to the fact that events come back newest-first? If you have a reading from your power meter, it tends to increase over time, and thus the delta would be negative.

``````day    meter    delta
4      123
3      111      -12
2      107      -4
1      101      -6
etc etc
``````

Try reversing search results with `reverse` in that case.

EDIT: had days in the wrong order.... fixed it.

Hope this helps,

Kristian

Builder

Turns out I was forgetting a space in my rtrim. It should have been eval TE=rtrim(Total_Energy, " kWH")
Thanks!

Builder

Half way fixed. The reverse worked. Any idea why I can't do a delta on the field that I used rtrim on?

eval TE=rtrim(Total_Energy, "kWH") | delta TE p=5 AS delta