Re: Fitting data to a curve

*To*: mathgroup at smc.vnet.net*Subject*: [mg73260] Re: Fitting data to a curve*From*: "ben" <benjamin.friedrich at gmail.com>*Date*: Fri, 9 Feb 2007 02:17:25 -0500 (EST)*References*: <eqengu$4gj$1@smc.vnet.net>

Hi Peter fit = FindFit[data, a x^2 + b y^2 + c x y + d x + e y + f, {a, b, c, d, e, f}, {x, y}] Please note Fit[] = linear fit = easy&stable = no initial guess required FindFit[] = nonlinear fit = subtle issue = initial guess helps a lot Always check your fitting results graphically. bye Ben Peter Jay Salzman schrieb: > I have a table of {x,y} data and a function: > > a y^2 + b x y + c x + d y + e = x^2 > > I'd like to do a least fit to determine the constants a, b, c, d, and e. I > think the function I want is Fit[] or FindFit[], but I can't coax Mathematica to do > this. I'm not entirely sure what to do with that x^2 since it has no > coefficient. > > I've never used these functions before; how can I do this least squares fit? > > Thanks!