Homey Community Forum

Negative number interpretation

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 unless the result is negative. Let’s say -700…
Can it be Homey asumes -700 is bigger tan 200?
Anyone has experience with a negative number as expression result?

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:


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.

Just reboot homey and try again.

Self healing software by rebooting? :wink: lol