Graph - Stop graphing when some value

[Asterix]

Hi,
is possibile to stop graphing when some value is returned?
In my case Ubiquiti device return -1000 of signal strenght when remote device is not connected via radio.

I need to stop graphing instead of get -1000

---

[tomaskir]

Use a transform script to return "null" when wrong value is received:

if ($1 < -100) {
  return null;
} else {
  return $1;
}

[Asterix]

When null is returned on the chart it goes a position itself as value 0

Version 3.6.303

Other methods?

[tomaskir]

Null means data collection error - no value will be stored in the DB, no value will be shown on the chart.
The DCI will show "<<ERROR>>" in Last Values.

If you want 0, simply return 0 in the transform script.

[Asterix]

I've tried, but in last value I get "0" instead of <<ERROR>>
This is the Transformation
return ($1 < -100) ? null : $1;

Why?

---

[Filipp Sudanov]

Try abort instead of return null:

if ($1 < -100) {
  abort;
} else {
  return $1;
}

[Asterix]

Thanks Filipp!

It Works ! !

[Asterix]

However, there is an anomaly 
If the chart is zoomed out, it tends to close the line between the previous and last retrieved value.
See in my example 1H Graph and 4H same graph

---

[victor]

Hi,

there is open change request for that: https://track.radensolutions.com/issue/NX-1826. Hopefully will fix it soon.

Best regards,
Victor