Time calculation hour addition

[vdiciacco (Vincent)]

Hello all,

I’m new in Home Assistant and I really appreciate this tool.
I have searched for hours now in this blog but without succeeding.
I want to calculate an hour from one reference hours (12:00) substract or add a number of hour comming from an input_value. I want to use this calculation in automation as I have several conditions before.

An example of what I have tried :

  - service: input_datetime.set_datetime
    data:
      time: {{ as_timestamp(strptime('12:00:00' , '%H:%M:%S') - ((states.input_number.piscine_nombre_fonctionnement_heure.state * 3600|int) / 2)) | timestamp_local }}      
    target:
      entity_id: input_datetime.piscine_debut_periode

Then I have switched to development tool and test several things like:

{{ as_timestamp(strptime(states.input_datetime.piscine_heure_pivot.state , '%H:%M:%S')) - as_timestamp(strptime(states.input_number.piscine_nombre_fonctionnement_heure.state|int , '%H')) }}

but I have still error ‘Template error: strptime got invalid input ‘6’ when rendering template’.

All help is welcome

Thank you in advance.

[akappa (Homer Assistant)]

Have you looked into this?

The EPIC Time Conversion and Manipulation Thread!

After seeing many threads on the forum asking for help with time conversions and calculations using time and realizing I generally had no real understanding of how time worked in HA I decided to dig in and try to figure it out. After over a week of internet and forum searches I think I’ve now got a lot of it figured out. I’m sure there is more that I don’t have here because sometimes “you don’t know what you don’t know”. So, since I didn’t know this stuff and because of the number of other pos…

[123 (Taras)]

  - service: input_datetime.set_datetime
    data:
      timestamp: >
        {{ (today_at('12:00:00') + timedelta(hours = states('input_number.piscine_nombre_fonctionnement_heure') | float(0))).timestamp() }}
    target:
      entity_id: input_datetime.piscine_debut_periode

If that fails to work (potentially because the template reports a timestamp value that includes the current date) then use this one:

  - service: input_datetime.set_datetime
    data:
      time: >
        {{ (today_at('12:00:00') + timedelta(hours = states('input_number.piscine_nombre_fonctionnement_heure') | float(0))).strftime('%H:%M:%S') }}
    target:
      entity_id: input_datetime.piscine_debut_periode

[vdiciacco (Vincent)]

@123

{{ (today_at('12:00:00') + timedelta(hours = states('input_number.piscine_nombre_fonctionnement_heure') | float(0))).strftime('%H:%M:%S') }}

Thank you very much to both of you!
@Taras, your code is the solution! It works fine. Thank you!
@akappa, thank you for sharing, I’ll read it carrefully (didn’t find it despite a lot of search…)

[123 (Taras)]

@vdiciacco

your code is the solution! It works fine. Thank you!

You’re welcome!

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