"cannot divide by 0" TinyMath error in Visual builder

[preetish_P (Preetish Pai)]

Hello Elastic community,

I am trying to build a metric in visual builder with 2 aggregations and a Math aggregation below them. But I am getting "Cannot divide by 0".

Below is my structure of data:

sr_number	some_other_column
sr1	abcd
sr1	abcd
sr1	abcd
sr1	abcd
sr2	abcd
sr2	abcd

I want to calculate : (Count of docs / unique of sr_number) .i.e. average per sr.

Below is the error I get when using a visual builder:

Surprisingly the two variables: params.count_of_events and params.count_of_srs have the correct values and work when used in other math functions.

E.g: when using add(a,b)

When using mutitply(a,b)

The variables show values individually too:

Has anyone faced such issues ? Any advice/workarounds is appreciated.

Thank you

[tsullivan (Tim Sullivan)]

It's not possible to divide by zero in math. As the visual builder calculates this expression for every value in the date histogram, there seems to be a section of time where the document count was zero for the query.

That said, which version of Kibana are you using? I am unable to reproduce this in 7.12.

In the mean-time, you could potentially use the clamp function to prevent this from being zero.

[preetish_P (Preetish Pai)]

Thank you @tsullivan

I am running ES v6.8.3. I wasn't aware that visual builder first creates a date histogram and then combines the result.

Using clamp function solved the error and now I am able to see the result of division.

However I have concerns with the accuracy of cardinality function as JSON input cannot be provided to visual builder as per this : Support json_input for visual builder or shard_size · Issue #23399 · elastic/kibana · GitHub

Hence I have decided to use Canvas dashboard for my implementation.