Hi
This seems to be an easy one, but I fail 
I am reading a modbus register and get an array back:

I am only interested in parts [0], [3] in order to get back a number: 3579
I was thinking of a split and join node combination
Splitting is easy, I get 4 messages back:

But how can i join/concatenate [0] and [3] in order to get the value 3579 back?
tnx 
Are you certain that is what you want? Seems a bit odd!
Anyhow, since your data is already an array, just concatenate the elements of interest in a function of change node.
Function:
msg.payload = parseInt(msg.payload[0].toString() + msg.payload[3].toString())
return msg
thank you, this does the job!
Yes, the values of 0 at position [1] and [2] are strange indeed, but this is what i get back...