Extract a value of an array

General
1

I want to extract the value of a specific position in an array that I am receiving from Inject sent from a Raspberry Pi with the protocol OPC - UA as 'int' variable but I do not know how to do it in Node - RED

Node-RED message payload

12/04/2019, 16:47:43node: Pressure BMP180 Sensor
ns=2;i=4 : msg.payload : array[2]
array[2]
0: 0
1: 97448

12/04/2019, 16:12:22[node: Pressure BMP180 Sensor](http://10.6.4.101:1880/#)msg : string[15]

"Bad data inject"

The value i want is the 97454

My configuration in the Inject is:

image

I need the value of the 1: position in the array

2

The docs have a page called "Working with messages"

https://nodered.org/docs/user-guide/messages

That has instructions on how to get at specific data you can display with a debug node.
Using that page and either a change node or a function node you should be able to do what you want to do.

3

The solution for my problem i think that way is correct, it's works for my situation and i share everyone

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image.png1359×413 47.2 KB

image
image

in the msg.payload.topic[1] the 1 is the position in array i want

if anyone has a suggestion to improve the programming I am open to suggestions

4

Hello, I have the same problem, could you send me the configuration of each node please? My email is antarita95@gmail.com please please help me

5

Welcome to the forum. It is not clear exactly what problem you have. Please explain in more detail. Have you read the document linked earlier? Also if you are a newcomer to node-red I recommend watching this playlist: Node-RED Essentials. The videos are done by the developers of node-red. They're nice & short and to the point. You will understand a whole lot more in about 1 hour. A small investment for a lot of gain.