Need some help from a template expert!

Configuration Frontend
1

Ok…Well this probably doesn’t need to be solved by an expert, but I’m still struggling with wrapping my head around this template stuff. I’m pretty sure what I want to do is really easy, I’m just struggling with getting it into an automation.

I have a input number helper entity that has a start value of “45”
I want to build an automation that everyday at a specific time (say 10pm) it subtracts that value by 1 until it the entity ultimately reaches 0. Can someone give me some direction of how to do the math inside an automation?

Any help is GREATLY appreciated!

2

If you have defined the steps of the helper with ‘1’, you could use input_number.decrement :


trigger:
  - platform: template
    value_template: "{{ states('sensor.time') == '10:00' }}"

 action:
  - service: input_number.decrement
    target:
      entity_id: input_number.xxxx

Alternatively:


- service: input_number.set_value
  data:
    value: |
       {% set in = states('input_number.x') |int(0) %}
       {{ in - 1 }}
   target:
    entity_id: input_number.x
2 Likes
3

You can just use a time trigger. OP might not even have a time sensor configured.

trigger:
  - platform: time
    at: "22:00"
4

Fair point. But I seem to remember that platform: time evaluates every second, sensor.time only once per minute.

5

I’m wondering why the time platform would need to evaluate at all? I confess I haven’t dug deep enough to figure out how the time platform actually works but I would have assumed the trigger would be initialized to fire at the time specified and Bob’s you’re uncle.

I’ve always tended to avoid templates if an alternative trigger/condition etc would do because I was under the impression the “native” platforms were more efficient.

Perhaps someone with a better understanding than myself will jump in and clarify. I’m curious now.

6

I believe that in an automation trigger in won’t make any difference because the trigger is being continuously evaluated in either case.

In a sensor using now() will be limited to evaluating once per minute.

And sensor.time only updates itself every minute.

But I don’t think using now() or sensor.time in a trigger limits the evaluation of the trigger to only once a minute.

7

Found the topic: With a single Automation, how do you turn lights on between two set times and then the lights off? - #22 by Mutt