y = a + bx + crx
Shah model.
Number: 4
Names: a, b, c, r
Meanings: a = offset, b = coefficient, c = coefficient, r = unknown
Lower Bounds: r > 0.0
Upper Bounds: r < 1.0
nlf_shah(x,a,b,c,r)
FITFUNC\SHAH.FDF
Exponential