Math operation

[paulzhdanov]

Hi @RavenSystem ,
Is there any chance to subtract values from temp sensors? Here's the example:
Solar collectors has 2 sensors, connected to "in" and "out" streams. For instance, is it possible to calculate: P = (t1-t2)V60*E where V is litters per minute (speed of stream) and E is heat capacity of water (4182 J/kg°C) ??
Now I use type 3 sensors (simplified example below) and send all data through network request to calculate, but having all calculations inside would be much-much better.

{
  "a": [
    {"t": 22, "g": 14, "n": 3},
    {"t": 22, "g": 14 , "n": 3, "u": 2}
  ]
}

Thanks in advance!

PS could you also give couple examples in Wiki of how math can be used?