Re: FindFit & NIntegrate
- To: mathgroup at smc.vnet.net
 - Subject: [mg96126] Re: FindFit & NIntegrate
 - From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
 - Date: Fri, 6 Feb 2009 04:11:04 -0500 (EST)
 - References: <gmecbc$acc$1@smc.vnet.net>
 
Hi,
and
model[x_?NumericQ,a_?NumericQ,b_?NumericQ,c_?NumericQ]:=
   NIntegrate[function[x_,t_,a_,b_,c_],{t,0,inf}];
will work. We had this 10^6 times before.
Regards
   Jens
hmalissa wrote:
> I want to use the FindFit function (or similar) to fit some
> experimental data:
> 
> fit=FindFit[data,expr,pars,vars]
> 
> Usually this works very well, but in this particular case the model
> expr consists of a NIntegrate over another function, like:
> 
> model[x_,a_,b_,c_]:=NIntegrate[function[x_,t_,a_,b_,c_],{t,0,inf}];
> fit=FindFit[data,model[x,a,b,c],{a,b,c},x]
> 
> FindFit now complains about non-numerical values; of course that makes
> sense.
> How can I force FindFit to do the fitting anyway?
>