Hi i think the solution is simple but i get stuck with adding up some values. I am a total N00b so please be patient. Situation: I get data from Domoticz via Mqtt. (works) I split the messages to get only the data i need (from 3 sensors) (works) Now the difficoult part. The output is like this: …

Here is my proposed solution based on the data in the first post. Join the three chunks together [26%20PM] In a change node, use jsonata to [12%20PM] 1 - change svalue1 from a string to a number payload ~> | $ | { "svalue1": $number(svalue1) } | 2 - sum up all occurances of svalue1 $sum(payl…

[image] R0yk3: I split the messages to get only the data i need (from 3 sensors) Do you mean that you are starting with one message from MQTT, then splitting that into three messages and then trying to put it back together to add up the bits you need? If so then don't do the split, just add …

Also see this post on how to share code or flow so that it is importable [image] How to share code or flow json FAQs To share code samples or flow json in this forum, you need to take care to format it properly so that it is displayed correctly. The easiest way to do that…

No, From mqtt i get loads of messages from all domoticz devices. From all these messages i filter out three (in this case idx23, idx24 , idx25). Then i want to add up the svalue1 from these three nodes.

OK, then you can use a Join node. Make sure the three messages have different topics and set the Join node to Manual, key/value pairs, using topic as key, and expecting three messages.

Been asked soooo many times. A simple search would uncover many threads. This one might give you a head start.... [image] Summing all msg.payload in a month General [image] Thank you. It works! slight_smile

[image] Colin: topic as key I think there is my problem? Following the explanation from the other article. using ,"stype":"Electric", as topic. i get the error "message missing key property 'msg.stype' - cannot ad to object" Sorry cannot post image couse i'm working on my phone.

I don't understand what you mean by [image] R0yk3: using ,"stype":"Electric", as topic Do you mean you have specified stype as the key? If so then the message must have a property stype, which it does not, according to the error. The most common way is to specify topic as the key and then …

This is one output of three: see first post. This is the debug message from the split node. {" Battery":255," RSSI":12," description":""," dtype":"Usage"," id":"0000000"," idx":25," name":"Delivery L3"," nvalue":0," stype":"Electric"," svalue1":"1710.0"," unit":6: } IDX is the unique v…

Set the debug node to Show Complete Message and show us what it says.

I wil do that at home. I'm now at work and the office firewall does not allow me to connect to my NodeRed. And at my phone it is not working well.

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Sum up three outputs from mqtt

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Colin 4 August 2019 11:09 3

Also see this post on how to share code or flow so that it is importable

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Sum up three outputs from mqtt

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