In Timelion is a secondary calculation possible? .trend () of .divide ().
Stated differently, How to calculate trend of Percent, where Percent is calculated using .divide () in Timelion, and is not a Scripted Field.
Timelion Sheet: is a secondary (TLnative) calculation possible
I believe all you need here is to add a trend at the end. Here's an example, since I can't see what your exact query is:
.es(q=error).divide(.es(q=*)).trend()
This will query error documents, divide them by the total and provide a percentage of errors, and then give you the linear regression of the percentage value over time.
Yes, while .trend() at end displays the linear regression line, we at the same time lose the .divide() tabulated Percent line of the raw data.
 Is there a way to display both the tabulated Percent line and Trend in the same TL graph
 Is there a Function for Polynomial Regression, or only Linear?
Thank you!

Resolved: At the end of the initial .es(q=error).divide(.es(q=)) appended a complete .es(q=error).divide(.es(q=)).trend(). This displays both Percent and Trend lines on the same graph

Is there a Function for Polynomial Regression, or only Linear?
As far as I know there's only a linear regression function, but I'm not the most wellversed Timelion user, so I could be wrong. I've asked someone else on the team that knows more about it, and I'll let you know what I learn.
UPDATE: poking through the code a little, it looks like .trend()
has a logarithmic mode. I'm basing that on this bit of code, which define the valid values for mode
.
UPDATE 2: perhaps you already know this, but just in case, you can find the trend function's docs here: https://github.com/elastic/timelion/blob/master/FUNCTIONS.md#trend