RE: curve-fitting

*To*: mathgroup at yoda.physics.unc.edu*Subject*: RE: curve-fitting*From*: fulling at sarastro.math.tamu.edu (Stephen A. Fulling)*Date*: Tue, 2 Mar 93 19:25:27 CST

>I am a Physics student at Fairfield University working on a >project now that requires a curve fit with the following form: >I = -I1*Exp[-t/T1] + I2*Exp[-t/T2] ... >I would appreciate any response or input. > Dan Kefford This is the answer you will like least, but according to Forman S. Acton, _Numerical Methods that Work_, this curve-fitting problem is notoriously ill-conditioned, and should not be attempted by ANY method other than experimental determination of the constants T1 and T2. (This is on pp. 252-253 of the first edition, in the "Interlude: What NOT to Compute".) I'm not a numerical analyst myself, so maybe Dan shouldn't just take my word for it. Would anybody else care to comment? S. A. Fulling Professor of Math, Texas A&M Univ.