Hey Guys, I have a flow that does a query on my energy provider and this returns an array with 120 objects in it (1/2 hour increments of pricing for electricity) The first x (arbitrary number) of these are in the past and are differentiated by a date and time, but more easily by a value in a field…

You can use JSONata in a change node payload.data.variablePricesAndRenewables[periodType = "FORECAST"][[0..19]] this will return first 20 items where field = FORECAST

I think a function node using findIndex and slice are you best bet. 2 lines of code.

Yeah i always find i come back to those two line functions later and have to remind myself how they work !! Plus now my son is getting into this and being a teenager i know he will not document any of this But time to roll the sleeves up i guess !! Thanks for taking the time to respond Craig

[image] craigcurtin: Yeah i always find i come back to those two line functions later and have to remind myself how they work Add comments :stuck_out_tongue_winking_eye:

HA HA !!! There is always one in every room!! Craig

WOW !! This JSONATA stuff is so powerful but it scares me to death ! Can you point me to a good beginner resource that i can work through to gt a handle on it ? Craig

Good is a subjective term here's where I go JSONata Documentation · JSONata ## Introduction and here is their exerciser, where you can add objects and expressions and test https://try.jsonata.org/

Good one thanks Man - can not believe how easy that one was (when you know how !) Craig

I suggest getting fully competent with js first. Anything can be done in js, only certain things can be done with jsonata.

[image] craigcurtin: Good one thanks Man - can not believe how easy that one was (when you know how !) JSONata is one of those things that is great until it isn't. Some things are really simple to comprehend, some are simple to do and the rest takes longer than learning JavaScript from scratc…

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Loop through an array and return index of a specific value

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craigcurtin 13 June 2021 04:16 12

Yep i hear both you and Colin - and was 1/2 way through (blundering) writing a function to do it, when the one line answer came in - to say i was impressed is a very big understatement !

Craig

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Loop through an array and return index of a specific value

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