Im trying to remove text from a string before sending it to a function node to then be converted over to a number. How would i do that? Im receiving data on serial from arduino and running that through a switch node. The string has text and then a number. The node im using to convert to a number doesnt like the text being in the string.
Both sensors come through with text then value. Example, "FLUE 124"
flue 124 is the payload
If they both are string/space/number there are several ways you could do this
- use a split function and split it on the space. Then you will get two msgs out of the split. drop the first and convert the second to a number to use
- you could use a function node to do the same thing
- get fancy and use a change node and the jsonata expression
$number($split(payload, " "))which in english says 'convert to a number the second part of the array created by spliting the men.payload on a space" (see doesn't that make it clear )
I ended up using a switch to sort and then a change to clean it up. Thanks for the help. Now onto the next project.
Node-red-contrib-string would be a good fit for this sort of thing if you're feeling lazy. It's my favorite crutch for proof of concept flows before I hand them off to other maintainers at work.
Isnt that string node basically the same thing im using my change node for?