Function h_tp 

pub fn h_tp(t: f64, p: f64) -> Result<f64, IAPWSError>

Calculates the water enthalpy in kJ/kg at a given temperature and pressure.

Temperature is assumed to be in K Pressure is assumed to be in Pa

Example

use rust_steam::{h_tp};
let h = h_tp(300.0, 101325.0).unwrap();