Hyperbolic interpolation method

The function can be approximated using the simplest rational function a 

Given three support points, the three parameters ai, U2, and Ui can be calculated 

Unlike Muller s method, this algorithm has a single solution  

Moreover, an interpolation with a rational function is usually preferable to using a polynomial function (Vol. 2 - Buzzi-Ferraris and Manenti, 2010b). 

The hyperbolic interpolation method is used when the root-finding classes from the BzzMalh library have performed three iterations. 

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