Using Psychrometric Charts in Labview to calculate Humidity?

I'm constructing a chilled mirror hygrometer for a college project and controlling it through labview. I will have the dew point temperature and dry dry bulb temperature I need to calculate the humidity through an algorithm or a look up table for psychrometric charts. can anyone help please.

Calculating wet bulb from dew point and ambient temperature is hard. It requires iterative algorithms. It is easy to calculate RH, absolute humity and enthalpy.
I have attached a paper I find usefull, "Numerical calculations of psychrometric properties on a calculator" by Singh, et al.
If I find an algoritm for wet bulb or figure out how to implement Singh's I will upload my VI.
Attachments:
psychrometric properties on a calc.pdf ‏71 KB

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