Hi all, is there an easy way for me to take two devices, both measuring temperature, subtract the two readings from each other and get that sum into its own widget?

I did touch on this some time ago and think I was advised analysis was the way to go, I did look into this at the time, saw it involved code and put the project down, until now.

Does anyone have such a piece of code they'd be kind enough to share so all I need do is change a few parameters to suit my case?

Many thanks.