Re: naive question

*To*: mathgroup at smc.vnet.net*Subject*: [mg92842] Re: naive question*From*: Albert Retey <awnl at gmx-topmail.de>*Date*: Tue, 14 Oct 2008 05:01:21 -0400 (EDT)*References*: <gcv7ku$e63$1@smc.vnet.net>

Francisco Gutierrez wrote: > Dear Friends: > I am using Fit within a function, and I want it to produce only a list of > coefficients, without the variables. > For example, if I plug into fit the following: Fit[{{1,2,3},{4,5,6},{7,8,9}},{1,x1,x2},{x1,x2}], > Mathematica produces: > 1.55556+0.555556 x1+0.444444 x2 > > I want to get only the following list: > {1.55556,0.555556,0.444444} > > It seem awfully simple, but I haven't managed. > How can I do it? > Thanks > Francisco Look at the functions CoefficientList and Coefficient. For your case you need some extra effort since CoefficientList arranges the coefficients in an other way: CoefficientList[ Fit[{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}, {1, x1, x2}, {x1, x2}], {x1, x2} ] hth, albert