SRichards2-FitFunc
Sigmoidal Richards function, type 2.
Number: 4
Names: a, xc, d, k
Meanings: a = top asymptote, xc = center, d = unknown, k = coefficient
Lower Bounds: a > 0.0, k > 0.0
Upper Bounds: none
nlf_srichards2(x,a,xc,d,k)
FITFUNC\SRICHAR2.FDF
Growth/Sigmoidal