How to get the first entry in a for loop

Configuration
1

Hello,

i trying to get only the first entry in a for loop,

{% for entity in  expand('group.diesel_fuel_sensors') | sort(attribute='state') | map(attribute='entity_id') | map('string')  | list %}
  {{states(entity)}} €
  {% endfor%}

thats a re my results

1.759 €
  
  1.799 €
  
  1.819 €

thank you

2

hi,
try this.

{% for entity in  expand('group.diesel_fuel_sensors') | sort(attribute='state') | map(attribute='entity_id') | map('string')  | list %}
  {%- if loop.first %}
  {{states(entity)}} €
  {% endif -%}
{% endfor%}
3

While it’s probably not going to cause an issue in this case, be aware that states are always strings so your sort is based on string comparison not a true numeric comparison.

{{ expand('group.diesel_fuel_sensors') 
| sort(attribute='state') 
| map(attribute='state')  | list | first }} €

In cases where you need a true numeric comparison, you can map the the states to a float before the sort:

{{ expand('group.diesel_fuel_sensors')  
| map(attribute='state')  | map('float', -1) 
| reject('lt', 0 ) | sort() | list | first }} €
1 Like
4

so one could do a ‘sort’ in-between then?
EDIT, sorry as not wanting to hijack the OP question but would max/min also work in string?
i.e. if I sort the list ascending and take the first, this would be ‘equal’ to min …or? (and vv for max)

5

Yes, OP could use min or max…

{{ expand('group.diesel_fuel_sensors') 
| map(attribute='state') | list | min }} €

Again if you map() to a float, the warning about string comparison no longer applies, but make sure to set a default that gives you a way to reject ‘unknown’ or ‘unavailable’ states.

{{ expand('group.diesel_fuel_sensors') 
| map(attribute='state') | map('float', -1)
| reject('lt', 0 ) | list | min }} €
1 Like
6

thank you that works well,
is it possible to display the attribute “station_name” which is related to the entity that displays the price?

I’ve tried a few things, but I always get “zero”.

here is for example one of the entities in the group

Unbenannt
Unbenannt690×730 94.5 KB

7

When you map to an attribute you effectively throw away all the other data from the state objects. You can use a second statement to select the proper entity based on the state derived from the first one.

{% set x = expand('group.diesel_fuel_sensors') 
| sort(attribute='state') | map(attribute='state') | list | first %}
{{ expand('group.diesel_fuel_sensors') 
| selectattr('state', 'eq', x) | map(attribute='attributes.station_name') | list | first }}

However, since the string comparison shouldn’t be an issue in your case, I would approach it as follows:

{% set x = expand('group.diesel_fuel_sensors') 
| sort(attribute='state') | list | first %}
{{ x.attributes.station_name }}
1 Like
8

ah okay i didn’t know that, that’s very helpful the information that he discards all other data.

Thank you very much that helped me a lot.