Commandline sensor offset

Configuration
1

Hi all!

I’m trying to use a little temper USB temp sensor accessed through a commandline sensor config, which works well (though unreliable updates, which I think is caused by the temper software being problematic) except the sensor has a large offset from the real temperature.

I’m using this configuration:

  - platform: command_line
    name: Room Temperature
    command: "temper-poll -s 0 -c"
    # If errors occur, make sure configuration file is encoded as UTF-8
    unit_of_measurement: "°C"
    value_template: "{{ value | float | round(1)}}"

which happily returns the value to 1 decimal place, which I assume has been converted into a float and rounded. If I put “float - 1.8” the value gets subtracted from the float-ified sensor response but the “round(1)” never gets applied, and I end up with a large number of decimals which is untidy. I assume I’m doing something dodgy with the order of operators, or approaching this entirely the wrong way. Any advice please?

2

Solved my own problem, so in case anyone else has this basic issue:
value_template: "{{((value | float)-1.8) | round(1)}}"
the calculation needs to be entirely encased in () before the round(1).