Re: Help with an error with NonlinearModelFit,

*To*: mathgroup at smc.vnet.net*Subject*: [mg99560] Re: [mg99525] Help with an error with NonlinearModelFit,*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Fri, 8 May 2009 00:13:55 -0400 (EDT)*Reply-to*: hanlonr at cox.net

Your model needs some explicit multipliers or spaces. {am, bm, cm} = { 1 + RandomReal[], 2 + RandomReal[], 8 + RandomReal[]} {1.48798,2.46428,8.91346} data = Table[{k, Log[am*k^2 + bm*k + cm + RandomReal[]]}, {k, 35}]; nlm = NonlinearModelFit[data, Log[a*k^2 + b*k + c], {a, b, c}, k]; nlm // Normal Log[1.4834808148709797*k^2 + 2.5953464393454073*k + 8.874882556234564] Bob Hanlon On Thu, May 7, 2009 at 8:12 AM , Anonymous wrote: > I'm trying to find a fit to a large set of data. > > Here are In[1], In[2]. > > In[1] := {{421.1, 6591.10}, ...}; > > (there are way more points, in fact there are 35 in total, but I don't > want to list them. All are real numbers.) > > In[2] := nlm = NonlinearModelFit[data, Log[ak^2 + bk + c], {a,b,c}, k] > > Then mathematica gives an error that basically says that the function > "is not a list of real numbers" > > Of course it is, so how do I fix this?