# Function to get multiple arrays
**URL:** https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457
**Category:** General
**Created:** [28 May 2020 19:52 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457 "2020-05-28T19:52:31Z")
**Posts on this page:** 11
**Page:** 1
### Author:  [@JamesMcCarthy79](https://discourse.nodered.org/u/JamesMcCarthy79)
#### Post date: [28 May 2020 19:52 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/1 "2020-05-28T19:52:31Z")
I have a Node-RED flow that uses an API request for my cycle routes. It returns a huge array up to 2000 points each for elevation, speed & grade. I would like to pull these values out and plot them onto a ride graph. Is there a way of being able to do this with a loop function as the amount will differ per trip and I donβt fancy having to pull each one out individually.
Example
Path for first elevation `payload.trip.track_points[0].e`
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### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [28 May 2020 19:55 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/2 "2020-05-28T19:55:21Z")
@JamesMcCarthy79
James, I assume that you have copied and pasted this post from [https://community.home-assistant.io/t/node-red-function-to-get-multiple-arrays/200024](https://community.home-assistant.io/t/node-red-function-to-get-multiple-arrays/200024)
The post above is missing the screenshot, please edit the post using the pencil icon and add your screenshot image.
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### Author:  [@JamesMcCarthy79](https://discourse.nodered.org/u/JamesMcCarthy79)
#### Post date: [28 May 2020 21:15 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/3 "2020-05-28T21:15:51Z")
@Paul-Reed I did indeed but felt maybe this was a better place to post my question.
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### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [28 May 2020 21:18 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/4 "2020-05-28T21:18:34Z")
> [@JamesMcCarthy79](#):
>
> I did indeed but felt maybe this was a better place to post my question
Yes, I agree π
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### Author:  [@hominidae](https://discourse.nodered.org/u/hominidae)
#### Post date: [29 May 2020 08:00 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/5 "2020-05-29T08:00:53Z")
...a ride graph would need a timestamp associated with each object on the array, wouldn't it?
I don't see this in your example.
Besides, the transformation to a chart datasets can be done in a function node, using js. Lopping over the array is not a problem in there...
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### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [29 May 2020 08:06 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/6 "2020-05-29T08:06:24Z")
> [@hominidae](#):
>
> Lopping over the array is not a problem in there...
In that case, can you share how it's done for the OP.
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### Author:  [@hominidae](https://discourse.nodered.org/u/hominidae)
#### Post date: [29 May 2020 08:11 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/7 "2020-05-29T08:11:07Z")
...I can share an example later, how I do that for other data from my setup.
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### Author:  [@JamesMcCarthy79](https://discourse.nodered.org/u/JamesMcCarthy79)
#### Post date: [29 May 2020 08:20 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/8 "2020-05-29T08:20:22Z")
> [@hominidae](#):
>
> ...a ride graph would need a timestamp associated with each object on the array, wouldn't it?
> I don't see this in your example.
In the example screenshot above you can see `payload.trip.track_points[0].t` is the timestamp in question
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### Author:  [@hominidae](https://discourse.nodered.org/u/hominidae)
#### Post date: [29 May 2020 11:14 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/9 "2020-05-29T11:14:29Z")
Ah, OK...didn't get that while browsing from my mobile π
I tried and quickly modify an example I use for another case, that might work for you.
At least it should give you some hints on how this might work.
Maybe @Paul-Reed is able to comment or improve, as I am not a JS guy π
```auto
let array = msg.payload.trip.track_points;
var time=0;
var elevation=0;
var speed=0;
var grade=0;
var i=0;
var chartarray = [[]];
for(let i = 0; i < array.length; i++) {
time = array[i].t;
elevation = array[i].e;
speed = array[i].x;
grade = array[i].y;
chartarray[0][i] = {"x":time,"y":elevation};
chartarray[1][i] = {"x":time,"y":speed};
chartarray[2][i] = {"x":time,"y":grade};
}
var chart = [{
"series":["Elevation", "Speed", "Grade"],
"data":chartarray,
"labels":[""]
}];
msg.payload = chart;
msg.topic = "trip"
return msg;
```
Info on how a dashboard chart works can be found here: [https://github.com/node-red/node-red-dashboard/blob/master/Charts.md](https://github.com/node-red/node-red-dashboard/blob/master/Charts.md)
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### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [29 May 2020 16:09 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/10 "2020-05-29T16:09:36Z")
> [@hominidae](#):
>
> Maybe @Paul-Reed is able to comment or improve, as I am not a JS guy
Neither am I π€
Perhaps @JamesMcCarthy79 can try with his data source, and let us know if there is a problem.
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### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [28 July 2020 16:09 UTC](https://discourse.nodered.org/t/function-to-get-multiple-arrays/27457/11 "2020-07-28T16:09:42Z")
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