hi i'm trying to make a chart for highest and lowest temperatures outside from an mqtt sensor. but am failing miserably, any sugestions where im going wrong would be great thanks martin [ { "id": "558a976d1540e55c", "type": "group", "z": "d3637ed3c66aa0d7", "sty…

@Colin , Yes, you are right and THE first message after the NEWDAY should send both Max and Min values. Maybe 2 outputs would be better, that way 2 messages could be sent. (Not at /to you) The code I posted was an EXAMPLE to show the structure of what to do. I'm not sure if missing one message …

hi thanks for the quick responses, unfortunately I'ts a bit over my head i tried adding the script to a function node , but received an error [image]

[image] Looks like you are missing the closing single quote on the name of your context variable.

There are two mistakes in the code I posted. That one and the line with previous_Min in it too. I didn't close the ' at the end of the line like with this line. Sorry.

no worries , ive done that but still getting warning , if (msg.topic == "NEWDAY") { // You need to reset values // you need to add stuff here. context.set('previous_max', 0) context.set('previous_min', 100) return // exit. } let previous_max = context.get('previous_max') || …

[image] montyfert: const temperature = msg.payload. remove the . after payload

Sorry folks. I am running a few different formatting rules and sometimes the punctuation rule sneaks in and adds . at the end of lines. Sometimes good, sometimes not.

thanks all for all the help your stars. martin

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Trying to chart high/low temp

Dashboard

Colin 28 November 2025 14:04 15

What warning?

1 Like

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Trying to chart high/low temp

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