Filter Data based on value for Count Query

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1

Hi I’m building a stat panel in Grafana to track the count of low gas trips. This is a binary point and I’m wondering if there is a way to filter the value of the point such that I only count when the value is 1 (i.e. the point trips). My base query below:

Count(FILTER ActiveMeasurements WHERE PointTag = ‘LOW_GAS’)

2

Hi,

You can try something like Count(IncludeRange(0.5, 2,FILTER ActiveMeasurements WHERE PointTag = ‘LOW_GAS’))

This would exclude any values below 0.5 and above 2

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3

Great! This is what I was looking for! I actually realize now that this type of point maintains a value of 1 the entire time that the point is tripped. In actuality, I would be counting the instances when the point switches from 0 to 1. Would it be possible to nest aggregate functions in Grafana? For example:

Count(IncludeRange(-0.5, -2, Difference(FILTER ActiveMeasurements WHERE PointTag = ‘LOW_GAS’)))

4

You have a few options here, They have slightly different performance implications and may behave differently in edge cases (e.g. 0 switches to 1 before your time range starts, but switches back post time range).

You can certainly nest aggregated functions, I would recommend one of the following:
ExceedsAt
Difference

Noting that the ExceedsAt will return more information, inlcuding the duration of the trip etc.

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