How to use complex math in rule condition?

[Exxonen]

Hi!

I have crawl space vent fan controlled by zwave switch.
I also have temp and humidity sensor in crawl space and outside.
Now I want to turn fan only if outside air will reduce crawl space humidity, i.e. dew point of outside air is lower than dew point of crawl space.
it can be computed, but it involves log and division.
how can I implement it using rule machine?
if not possible - can you please point me in right direction?

thanks!

[Sebastien]

This is how I calculate dew points. Note that I use Celcius.

[rlithgow1]

@Sebastien

This is how I calculate due points.

Is that canuck for dew?

[Sebastien]

Haha! That is I don’t know how to spell for dew. Fixed.

[jpcurcio]

In Quebec, wouldn't it be "deux"?

[Sebastien]

Or maybe “doux”.

[rlithgow1]

@Sebastien

Or maybe “doux”.

[Exxonen]

Thanks a lot! this helped!

Andrey

PS. I'm from BC, so I am using units that make sense too.

[rlithgow1]

@Exxonen

PS. I'm from BC, so I am using units that make sense too.

Bakersfield California? Cool...

[Exxonen]

Been in California, but not in Bakersfield
BC where people use metric system is British Columbia

[rlithgow1]

@Exxonen

BC where people use metric system is British Columbia

I got that, just wanted to make the dad joke,,..

[Exxonen]

Perfect day for dad's jokes!