I am trying to do a simple subtraction of time in a function node. The elements of time include; current time, minus 'time since last motion'. Both of these are formatted in epoch time. The issue that I am having is that 'time since last motion' - only sends a piece of data every time motion is se…

[image] bakman2: The join node will need to be configured properly [image] JHScen: I have done that, however when I run it - there is no error, but there is also no output Then you dont have it set up correctly. Do both streams going into join have a unique topic? Have you set the jo…

As messages arrive at different times you would have to join the node https://cookbook.nodered.org/basic/join-streams you could also access the current time in the function node [image] JavaScript Date Objects W3Schools offers free online tutorials, references and exercises in all the …

I shall give it a try! Thank you!

basically you want to calculate the elapsed time between two mqtt msgs coming from the "Pull" node ? a single Function node can remember the last timestamp by saving it in Context and then doing a calculation Here is an example: [{"id":"1e385cb4f3e69b70","type":"inject","z":"54efb553244c241f","na…

Still seems to give me a NaN reading when I put them through the function node to do the subtraction

NaN means 'not a number' is it arriving as a string ?

It is - if I put it straight to a debug node, it comes through as expected. It just seems to be when it goes through the function node to do the subtraction that something unexpected happens

what does the function node code look like ?

Within the function node I have the following: msg.payload.timeconvert = (msg.payload.time / 1000) - msg.payload.tsml; return msg; I have tried using the join node as suggested above, but I am having an issue using the join node as it doesn't seen to want to connect the data as one is from MQTT an…

The join node will need to be configured properly, ie. number of expected input messages and how they will be combined.

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Epoch Time subtraction

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JHScen 19 January 2022 12:17 5

One of the msgs is MQTT the other is just a time stamp in Epoch format..

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Epoch Time subtraction

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