I created a flow which reeds my solar panel production and compares this with the house usage. Reason is to power on some things only while there is overproduction. I am struggling with a negative number of an expression. IF (usage - production) is more than 200 IS TRUE THEN… This is working unl…

Hi, what happens when you use brackets around the difference?

Gives the same result. Somehow Homey thinks -700 is bigger than 200…

Try {{usage - production}} Put calculations always between curly braces (accolades)

When the result is positive the calculation is OK, but will try tomorrow with the accolades. Tnx!

Tried with the {…} even with double {{…}}, but still the same behaviour. A bug in the Homey calculation engine?

I think you are right. This morning {{expression}} didn’t work anymore. There was an error message that a card was missing a tag. After a homey reboot it worked again. See pictures below: [image] [image]

I also tried some other things but Homey does not do the right thing with negative numbers. They just compare the number and not if it is a + or - number. How does this work to file it as a bug? Contact Homey support? Or do they read with us here?

You can file a bug here: https://support.athom.com/hc/en-us/requests/new

The post below will help you to “solve” the bug. [image] Help with flow - missing TAG in flowcard error? Questions & Help @Ton_Meek Yes, you were right. A reboot solves this issue. The flow can be saved and does not return a ‘Missing TAG in flowcard’ message. Just re…

Self healing software by rebooting? :wink: lol

Negative number interpretation

Flows

Ton_Meek September 24, 2019, 1:54pm 10

The post below will help you to “solve” the bug.

Just reboot homey and try again.

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Negative number interpretation

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