Add a Range Filter profile

[jimtng]

Add a range-filter profile to allow/discard values inside a given range.

Example .items file:

// Simple range - allows 0 - 30
Number MyNumber { channel="xxxx" [profile="system:range-filter", range="[0 .. 30]" }
// exclusive boundaries with ( and ) discards 0 and 30
Number MyNumber { channel="xxxx" [profile="system:range-filter", range="(0 .. 30)" }
// exclusive boundaries only on beginning/end: accepts 0, discards 30
Number MyNumber { channel="xxxx" [profile="system:range-filter", range="[0 .. 30)" }

// Supports "inverted" range: discards what's in the given range
Number MyNumber { channel="xxxx" [profile="system:range-filter", range="[0 .. 30]", action="discard" }

// Supports begin-less and end-less range, i.e. for a simple "greater than / less than" filter
//   allow anything up to and including 30
Number MyNumber { channel="xxxx" [profile="system:range-filter", range="[ .. 30]" }
//   allow anything 30 or above
Number MyNumber { channel="xxxx" [profile="system:range-filter", range="[30..]" }

// multiple ranges
Number MyNumber { channel="xxxx" [profile="system:range-filter", range="[0 .. 30], [60..80]" }

// Dimensioned item/channel
Number:Temperature MyTemp { channel="xxxx" [profile="system:range-filter", range="[-50 °C..60 °C]" ] }
// mix units in the range
Number:Temperature MyTemp { channel="xxxx" [profile="system:range-filter", range="[-50 °C..140 °F]" ] }

Config in the Main UI:

[openhab-bot]

This pull request has been mentioned on openHAB Community. There might be relevant details there:

https://community.openhab.org/t/reasonableness-constraints/145795/26

[rkoshak]

I suspect if you make it someone somewhere will use it. The range as implemented can handle most common use cases. I'm not sure how one would implemented outlier except though a moving-average, though maybe I'm just not 100% back mentally after being ill all last week.

Thinking through some use cases:

• reject values that are obviously out of range (e.g. temp sensor reporting 5000 °C)
• reject values that are a jump beyond what's reasonable from the last value (e.g. temp sensor jumps from 5 °C to 30 °C)
• reject values that are too small of a change from the last one (smooth out values from a noisy sensor)
• ignore a discrete state always (e.g. maybe someone has a Switch Item linked to a channel that provides ON, OFF, STANDBY and they want to just ignore STANDBY)

It makes a lot of sense to have one profile that can handle all these (and any others I've not thought of.

[jimtng]

I'm not sure how one would implemented outlier

I've presented several options in the forums, all of which can be implemented, giving user the choice of method to use

• Inter Quartile Range method
• Standard deviation as the range (i.e. only accept data if it's below the standard deviation) method
• A fixed "deviation" method - check how much it deviates from the median of the collected samples - basically the same way HomeAssistant does it
• Others can be added in the future

Thinking through some use cases:

• reject values that are obviously out of range (e.g. temp sensor reporting 5000 °C)
• reject values that are a jump beyond what's reasonable from the last value (e.g. temp sensor jumps from 5 °C to 30 °C)

Either a range or an outlier filter can handle this

• reject values that are too small of a change from the last one (smooth out values from a noisy sensor)

A moving average filter can handle this - but it's different from an outlier filter.

• ignore a discrete state always (e.g. maybe someone has a Switch Item linked to a channel that provides ON, OFF, STANDBY and they want to just ignore STANDBY)

Currently this PR only supports numeric channels / items.

Perhaps for this, we need a different type of filter, e.g. value-filter which provides a list of allowed (or forbidden/blocked) discrete values, e.g. a comma separated list of values, which would be suitable for string / non numeric items.

For numeric items, it can be done using this range profile [10..10], [15..15] to allow/reject 10 and 15.

[crnjan]

Will something like https://www.home-assistant.io/integrations/filter/#time-simple-moving-average also be supported? Currently I'm using something like

  var item = items.getItem(name);
  var from = time.ZonedDateTime.now().minusMinutes(10);
  var average = item.history.averageSince(from);

to smoothen my temperature readings but having a profile to do the job would be imho nicer ...

[jimtng]

Will something like https://www.home-assistant.io/integrations/filter/#time-simple-moving-average also be supported? Currently I'm using something like

  var item = items.getItem(name);
  var from = time.ZonedDateTime.now().minusMinutes(10);
  var average = item.history.averageSince(from);

to smoothen my temperature readings but having a profile to do the job would be imho nicer ...

I think that belongs in a separate profile (to be created) called smoothing-filter with the option of various ways of achieving that, e.g. https://en.wikipedia.org/wiki/Moving_average

[jimtng]

Closing this because it needs to go into an addon