John Kuszewski (johnk at spasm.niddk.nih.gov) wrote: : I = exp(-kf1 * tf) * (kex/(kex + kf2)) * : (1 - exp( -(kf2 + kex)* tex)) : kex is a known constant. : I, tf, and tex are known variables. : I need to optimize values of kf1 and kf2 against : sets of several (I, tf, tex) values. The NONLIN function in SYSTAT will take care of this problem quite easilly