Bunching mqtt data before passing to next node

[Leo]

Hi there,

I have an mqtt in node that receives every second a value which is send into a function node.
Now I want to get 60 values (every minute) from the mqtt, average them and only send the average to an influx database. How can I do that ? Looked for nodes like complete, join and so on, but I cant get it to work. Any ideas how I can achieve this ?

Tkx
Leo

[OliverWieland]

What you are looking for is called moving average

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[Colin]

Have a look at the Smooth node.

[Leo]

Hi Oliver,
Tkx for you reply, but I seems my question was not well put. I only want to send one value per 60 sec send to the influx database.
Leo

[marcus-j-davies]

This sounds like a job for the delay node.
set it to rate limit, with dropping intermediate messages, or queue them.

[OliverWieland]

Then you could combine my solution with the one from @marcus-j-davies

[ralphwetzel]

Citing a recent user comment ...

@OliverWieland

I know there are a lot of possibilities to solve my problem.

... I'd emphasize to look at the smooth node - as @Colin already proposed: It provides several forms of averaging & the functionality to reduce to 1 message per x messages.

[OliverWieland]

Sorry, didn't know that one...

[Leo]

Got it to work thanks to your input guys, much appreciated !

Tkx
Leo