Filtering in Trigger Expression

[tarunwadhwa13]

I am stuck in this issue and honestly appreciate any help !!

Context:

We are trying to apply trendavg function in Zabbix trigger expressions to calculate change in value. There are many userparameters (curl statements) which pull data from source, apply jq and return a numeric value

Imp: In case source from where value is pulled is down, user parameter function returns -1


Problem:

Trendavg is basically consuming that -1 value as well to diluting the actual average. Average is falling, creating a lot of noise in system


Question: Is it possible to filter values in trigger expression to only include positive values in average? Any hack to filter out values and then try to average?

Background Information:
Zabbix Version: 5.4

[tarunwadhwa13]

0 will also neutralize value. I tried discarding value but then I see a lot gaps in data. I mean, seeing the latest values for item, there are missed timestamps and it is difficult to find out whether data was discarded or there was issue zabbix polling queue.

[cyber]

Preprocessing? "in range" and either discard values or replace with 0 .. for example.