Generalized hyperbola function.
Reference: Ratkowksy, David A. 1990. Handbook of Nonlinear Regression Models. Marcel Dekker, Inc. 4.4.7
Number: 4
Names: a, b, c, d
Meanings: a = coefficient, b = coefficient, c = coefficient, d = coefficient
Lower Bounds: none
Upper Bounds: none
nlf_hyperbolagen(x,a,b,c,d)
FITFUNC\HYPERGEN.FDF
Hyperbola