Re: Question on looping FindRoot
- To: mathgroup at smc.vnet.net
- Subject: [mg86702] Re: Question on looping FindRoot
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Wed, 19 Mar 2008 05:22:37 -0500 (EST)
- Organization: Uni Leipzig
- References: <fro35c$i3b$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
Hi, and you know the difference between Set[] "=" and Equal[] "==" ? Regards Jens PS: Using % and %% .. is not a good idea, because it is used in the command line variant of the Mathematica kernel but in a notebook interface it will cause many mystic errors. Alessandro Tavoni wrote: > Hello, > > this is probably due to my being relatively new to Mathematica, > but I cannot succesfully execute a loop with FindRoot. > when I give the following input (I have converted it to input form): > > > ClearSystemCache[] > ratio = 1 > \[Lambda] = 1.4 > k = 1 > Overscript[U1, DifR] = > Table[14 - 6*\[Beta]1, {\[Beta]1, 0, 0.5/ratio, 0.5/ratio/1000}]; > Overscript[U1, UifR] = > Table[4 - 18*\[Alpha]1, {\[Alpha]1, 0, 0.5, 0.0005}]; > Overscript[U1, UifL] = > Table[10 - 2*\[Alpha]1, {\[Alpha]1, 0, 0.5, 0.0005}]; > Overscript[U1, DifL] = > Table[9*(\[Alpha]1 + 1)^0, {\[Alpha]1, 0, 0.5, 0.0005}]; > Overscript[U2, LifD] = > Table[9*(\[Alpha]1 + 1)^0, {\[Alpha]1, 0, 0.5, 0.0005}]; > Overscript[U2, RifD] = > Table[8 - 6*\[Alpha]2, {\[Alpha]2, 0, 0.5, 0.0005}]; > Overscript[U2, RifU] = > Table[22 - 18*\[Beta]2, {\[Beta]2, 0, 0.5/ratio, 0.5/ratio/1000}]; > Overscript[U2, LifU] = > Table[12 - 2*\[Beta]2, {\[Beta]2, 0, 0.5/ratio, 0.5/ratio/1000}]; > For[k = 1, k < 5, k++, > eq1 = Pu == (Exp[\[Lambda]*(Overscript[U1, UifL][[k]]*Ql + > Overscript[U1, UifR][[k]]*(1 - Ql))]/ > (Exp[\[Lambda]*(Overscript[U1, UifL][[k]]*Ql + > Overscript[U1, UifR][[k]]*(1 - Ql))] + > > Exp[\[Lambda]*(Overscript[U1, DifL][[k]]*Ql + > Overscript[U1, DifR][[k]]*(1 - Ql))]))*eq2 = > Ql == (Exp[\[Lambda]*(Overscript[U2, LifU][[k]]*Pu + > Overscript[U2, LifD][[k]]*(1 - Pu))]/ > (Exp[\[Lambda]*(Overscript[U2, LifU][[k]]*Pu + > Overscript[U2, LifD][[k]]*(1 - Pu))] + > > Exp[\[Lambda]*(Overscript[U2, RifU][[k]]*Pu + > Overscript[U2, RifD][[k]]*(1 - Pu))]))*Prob = > FindRoot[{eq1, eq2}, {Pu, 0}, {Ql, 0}]*ProbUp[[k ;; All]] = > %[[1]]*ProbLf[[k ;; All]] = %%[[2]]] > > > I'm told Symbol::argx: Symbol called with 0 arguments; 1 argument is > expected. > and: Set::write: Tag Times in > > Thank you so much in advance, > > Alessandro > -- > Alessandro Tavoni > Ph.D. candidate > Advanced Scool of Economics, University of Venice "C=E0 Foscari" > http://venus.unive.it/alessandro.tavoni