Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2013

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Constraint definition is not valid: WHY?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg131383] Re: Constraint definition is not valid: WHY?
  • From: Alessandro Bolli <aless.bolli at gmail.com>
  • Date: Tue, 2 Jul 2013 00:48:22 -0400 (EDT)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com
  • Delivered-to: l-mathgroup@wolfram.com
  • Delivered-to: mathgroup-outx@smc.vnet.net
  • Delivered-to: mathgroup-newsendx@smc.vnet.net
  • References: <kqrite$4a6$1@smc.vnet.net>

Il giorno luned=EC 1 luglio 2013 11:42:06 UTC+2, Alessandro Bolli ha scritto:
> I am tring to use Nmaximize in Mathematica This is How I proceeded:
>
>
>
> 1) define a list of parameters: Par = {a->1, b->3, etc};
>
>
>
> 2) define two functions: f1: v1=express./Par f2: v2=express./Par
>
>
>
> After this the expression are numerical except for the variables:
>
>
>
> V1=f(e1,x) and V2=f(e2,x)
>
> The objective function to be maximized is V1/(e1+e2) I defined the constraint as constr=V1-V2;
>
>
>
> then I used the Nmaximize:
>
>
>
>  NMaximize[{objopt > 0, constr == 0}, {e1, e2, x}, Method -> NelderMead]
>
> I obtained the following error:
>
>
>
> NMaximize::bcons: "The following constraints are not valid: "expression".  Constraints should be equalities, inequalities, or domain specifications involving the variables"
>
>
>
> I checked that only those variables are present in the constraint and objective function (other are numerical parameters) I do not understand why this error appears can someone help me?
>
>
>
> Thank you
>
>
>
> Alex

I solved the many errors I made. I am a real noob with mathematica. Thank you



  • Prev by Date: Re: Cashflow and TimeValue Question
  • Next by Date: Rather simple function returns curious result. Explanation requested.
  • Previous by thread: Re: Constraint definition is not valid: WHY?
  • Next by thread: Re: eliminating script level change in a math cell...