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Re: squared norm in Mathematica

  • To: mathgroup at smc.vnet.net
  • Subject: [mg85796] Re: squared norm in Mathematica
  • From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
  • Date: Fri, 22 Feb 2008 07:24:03 -0500 (EST)
  • Organization: Uni Leipzig
  • References: <fpkvh4$hmo$1@smc.vnet.net>
  • Reply-to: kuska at informatik.uni-leipzig.de

Hi,

Set[] written as "=" has nothing to do with Equal[]
written as "==" and FindMinimum[] need Equal[] and
*not* Set[]

Regards
   Jens

syed qasim Ali wrote:
>   Dear Sir,
>   My problem was  actually
>   
>   ||SX||^2
>   i was trying it as multiobjective optimiztaion in Mathematica but i g=
ot to know that it can be programmed as single objective ....
>   
>   
>   ||SX||^2=(a11*x1 + a12*x2 + a13*x3)^2 + (a21*x1 + a22*x2 +
> a23*x3)^2 + (a31*x1 + a32*x2 + a33*x3)^2.
>   
>   
>   therefore my problem becomes
>   
>    x1 >= 0.52, <= 1.47;
>  x2 >= 0.52, <= 1.47;
>  x3 >= 0.52, <= 1.47;
>  x4 >= 0.52, <= 1.47;
>   
>  
> 
>   minimize : ( ((-0.22*x1)+(0.13*x2)+(-0.09*x3)+(0.07*x4))^2 +
> ((-0.13*x1)+(0.09*x2)+(-0.07*x3)+(0.058*x4))^2 +((-0.09*x1)+(0.07*x2)+
> (-0.058*x3)+(0.049*x4))^2);
>   
>  
> subject to:
>           -4+x1^2+x2^2+x3^2+x4^2=0;
>   
>   
>   IN Mathematica it becomes
>   
>   FindMinimum[{(-0.22 g1+0.13 g2-0.09 g3+0.07 g4)2+(-0.13 x1+0.09 x2-0.=
07 x3+0.058 x4)2+(-0.09 x1+0.07 x2-0.058 x3+0.049 x4)2,-4+x12+x22+x32+x42=
=0&&0.52=A3x1=A31.47,0.52=A3x2=A31.47,0.52=A3x3=A31.47,0.52=A3x4=A31.47=
},{x1,x2,x3,x4}]
>   
>   
>   i have this  result when i tried this problem in Mathematica ....i gu=
ess Mathematica can handle this problem
>   
>   Set::write : Tag Plus in
>   -4+x12+x22+x32+x42 is Protected
>   FindMinimum::eqineq : Constraints in {0,0.52=A3x1,0.52=A3x2,0.52=A3x3=
,0.52=A3x4,x1=A31.47,x2=A31.47,x3=A31.47,x4=A31.47} are not all equality =
or inequality constraints. With the exception of integer domain constrain=
ts for linear programming, domain constraints or constraints with Unequal=
 (!=) are not supported.
>   
>   i donot understand where the fault lies ...when i have only one objec=
tive function
>   
>   
>   thanx
>   
>


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