Re: NIntegrate v.s. NonlinerFit
- To: mathgroup at smc.vnet.net
- Subject: [mg25840] Re: NIntegrate v.s. NonlinerFit
- From: "Allan Hayes" <hay at haystack.demon.co.uk>
- Date: Wed, 1 Nov 2000 01:25:30 -0500 (EST)
- References: <8tdpgf$5ns@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Carmelo, One observation: try NumberQ in place of Number. -- Allan --------------------- Allan Hayes Mathematica Training and Consulting Leicester UK www.haystack.demon.co.uk hay at haystack.demon.co.uk Voice: +44 (0)116 271 4198 Fax: +44 (0)870 164 0565 "Carmelo La Rosa" <clarosa at dipchi.unict.it> wrote in message news:8tdpgf$5ns at smc.vnet.net... > Hi, > my problem is the following: > I have difined a function as following, in order to use in a nonlinear > bestfit containing a numerical integration (work on WinNT 4.0 and > Mathematica 3.0) > > <<Statistics`NonlinearFit` > pars={a,b,c}(*parameters for the fit*) > pars0={.......}(*starting parameters of pars*) > A(X)=Exp[-a/X] > K(X)=Exp[-b/X] > > f[(T_)?Number,(a_)?Number,(b_)?Number,(c_)?Number]:= > (b*K(T)/(K(T)+1)^2)*Exp[-costant*Module[{X},NIntegrate[A(X)*K(X)/(K(X)+1)),{ X,Ton,T}] > > the output is a error messagge: > > NIntegrate::"nlim": "\!\(X$1\) = \!\(T\) is not a valid limit of > integration." > NIntegrate::"nlim": "\!\(X$1\) = \!\(T\) is not a valid limit of > integration." > NIntegrate::"nlim": "\!\(X$1\) = \!\(T\) is not a valid limit of > integration." > General::"stop": > "Further output of \!\(NIntegrate :: \"nlim\"\) will be suppressed > during \ > this calculation." > > In[19]:= > > fitted=NonlinearFit[data,Cp[T,pars],pars,T,MaxIterations->3000, > Errors\[Rule]1.0,InitialGuess\[Rule]pars0,ProgressTrace\[Rule]True] > > NonlinearFit::"toomany": > "Too many variables have been provided for the size of the data; > given \!\ > \(2\)-tuples for data, given \!\(4\) variables." > > Any assistance will be greatly appreciated. > > Carmelo la Rosa > > > -- > ____________________________________ > ------------------------------------ > Carmelo La Rosa > Department of Chemical Science > Laboratory of Biophysical Chemistry > University of Catania > V.le A. Doria 6, 95125 Catania > ITALY > Tel1. ++39-95-7385114 > Tel2. ++39-95-339572 > Fax ++39-95-580138 > E-Mail clarosa at dipchi.unict.it > ------------------------------------ > ____________________________________ > > >