Does anybody know how I can round the number being derived from state down to two decimals?
label: '[[[ return states["sensor.eve_room_237a_temperature"].state + "°C" ]]]'
I’ve tried a variety of things like .round(2), .round(), | round() but no luck as yet.
Try with
'{{ states.sensor.eve_room_237a_temperature.state | round(2) }}' °C
Sadly, this just prints it as a string.
Moving it to a value_template then results in [Object object]
So try with:
label: '[[[ return states["sensor.eve_room_237a_temperature"].state | float | round(2) + "°C" ]]]'
Yeh, I tried this alreay too 
it just errors and the card disappears lol. It’s a real brain teaser this one
Can you print here the whole card please?
novelty? I’m interested too
I finally managed it, I don’t know if you solved it, I’ll write it anyway, maybe it can be useful to someone
label: '[[[ return Math.round((states['sensor.eve_room_237a_temperature'].state)) + "°C" ]]]'