[Getdp] Method of moments

Lars Rindorf lhr at com.dtu.dk
Thu Jan 17 12:35:29 CET 2008


Dear Ruth
 
That is strange. What OS do you use? 
 
I use windows xp. I have just installed the latest version of getdp on another computer running xp, and the error message is exactly the same. The complete message in the message consol is:
Info    : -------------------------------------------------------
Info    : Gmsh version   : 2.0.8
Info    : Build OS       : CYGWIN_NT-5.1-no-cygwin
Info    : Build options  : GSL TRIANGLE NETGEN TETGEN JPEG PNG ZLIB MATHEVAL ANN OCC 
Info    : Build date     : Fri Jul 13 10:18:46 RDT 2007
Info    : Build host     : winxp
Info    : Packager       : Administrator
Info    : Home directory : C:\DOCUME~1\lhr\LOCALS~1\Temp/
Info    : Launch date    : Thu Jan 17 12:35:01 2008
Info    : Command line   : C:\Documents and Settings\lhr\My Documents\getPD\gmesh\gmsh.exe C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.msh 
Info    : -------------------------------------------------------
Info    : Reading 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.msh'
Info    : 2497 vertices
Info    : Vertex numbering is dense
Info    : 4798 elements
Info    : Read 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.msh'
Info    : Calling 'C:/Program Files/getPD/getdp.exe  "C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.pro" -socket "127.0.0.1:44122"'
GetDP   : Loading   : Problem definition 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.pro'
GetDP   : Info      : Available Resolutions
GetDP   : (1) res_dirichlet
GetDP   : Info      : Available PostOperations
GetDP   : (1) po_dirichlet_E
GetDP   : (2) po_dirichlet_scat
GetDP   : E n d
Info    : Calling 'C:/Program Files/getPD/getdp.exe "C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.pro"  -pre res_dirichlet -socket "127.0.0.1:44122"'
GetDP   : Loading   : Problem definition 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.pro'
GetDP   : Info      : Selected Resolution 'res_dirichlet'
GetDP   : Loading   : Geometric data 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.msh'
GetDP   : Info      : System 'A' : Complex, Frequency = 0 Hz
GetDP   : P r e - P r o c e s s i n g . . .
GetDP   : Operation : Treatment Formulation 'form_dirichlet'
GetDP   : Resources : cpu 0.078125 s 
GetDP   : E n d   P r e - P r o c e s s i n g
GetDP   : E n d
Info    : Calling 'C:/Program Files/getPD/getdp.exe "C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.pro"  -cal -socket "127.0.0.1:44122"'
GetDP   : Loading   : Problem definition 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.pro'
GetDP   : Info      : Selected Resolution 'res_dirichlet'
GetDP   : Loading   : Geometric data 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.msh'
GetDP   : Info      : System 'A' : Complex, Frequency = 0 Hz
GetDP   : P r e - P r o c e s s i n g . . .
GetDP   : Loading   : Pre-Processing data 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\2Dscat.pre'
GetDP   : Resources : cpu 0.0625 s 
GetDP   : E n d   P r e - P r o c e s s i n g
GetDP   : P r o c e s s i n g . . .
GetDP   : Operation : Generate[A]
GetDP   : Solver    : Loading parameter file 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\solver.par'
GetDP   : Info      : Setting System {A,b} to zero
GetDP   : Error     : Segmentation violation (invalid memory reference)

Thanks
Lars Rindorf

________________________________

From: Ruth V. Sabariego [mailto:r.sabariego at ulg.ac.be]
Sent: Thu 1/17/2008 11:44 AM
To: Lars Rindorf
Cc: Olivier Castany; getdp at geuz.org
Subject: Re: [Getdp] Method of moments



Dear Lars,
You do have to include the Dof in the definition of the integral
quantity.  E is a degree of freedom, so you have to indicate it even if
appears in an integral quantity.
The 'so-called' Dof flag is not necessary if you are going to use the
integral quantity in a postprocessing.

 { Name form_dirichlet; Type FemEquation;
    Quantity {
      { Name E;  Type Local;     NameOfSpace nodal_form0;}
      { Name E2; Type Integral ; NameOfSpace nodal_form0;
        [ Helmholtz[]{2D,k0} * Dof{E} ]; In scat; Jacobian Jac ;
Integration I1 ; }
   }
    Equation {
      Galerkin {      [  Dof{E},{E} ]; In Domain; Integration I1;
Jacobian Jac;}
      Galerkin {      [  -inc[],{E} ]; In Domain; Integration I1;
Jacobian Jac;}
      Galerkin {      [  Dof{E2},{E} ]; In Domain2D; Integration I1;
Jacobian Jac;}
      /*  g d^2 h - g k^2 h = -dg*dh - k^2 g*h*/
       }
  }

I've just tried your files with my Getdp and Dof in the integral
quantity definition mand they work here.
Regards,
Ruth



Lars Rindorf wrote:
> Dear Olivier
> 
> I tried to do this, but the message consol returns
> GetDP   : Operation : Generate[A]
> GetDP   : Solver    : Loading parameter file 'C:\Documents and Settings\lhr\My Documents\getPD\Greens_sq\solver.par'
> GetDP   : Info      : Setting System {A,b} to zero
> GetDP   : Error     : Segmentation violation (invalid memory reference)
>
> In the getpd manual it is describes that the integral type is assembled before the calculation, and thus can't be a degree of freedom (dof). Before the calculation the field is zero, and thus the integral term is effectively ignored.
> 
> But I don't really know what to do from here. I have attached the .pro, .geo, and solver paramter files, so you can play with it.  Note, that when you postproces the scattered field, i.e. the integral with the green's function, the computed E-field is used.
> 
> Thanks
> Lars
> 
> 
>
> ________________________________
>
> From: Olivier Castany [mailto:castany at quatramaran.ens.fr]
> Sent: Wed 1/16/2008 11:12 PM
> To: Lars Rindorf; getdp at geuz.org
> Subject: Re: [Getdp] Method of moments
>
>
>
>  
>>   { Name form_neumann; Type FemEquation;
>>     Quantity {
>>       { Name E;  Type Local;     NameOfSpace scalar;}
>>       { Name E2; Type Integral ; NameOfSpace scalar;
>>         [ Helmholtz[]{2D,k0} * {E} ];
>>         In feed; Jacobian Jac ; Integration I1 ; }
>>    }
>>     Equation {
>>       Galerkin {      [ Dof{E},{E} ]; In Domain; Integration I1; Jacobian Jac;}
>>       Galerkin {      [ -inc[],{E} ]; In Domain; Integration I1; Jacobian Jac;}
>>       Galerkin {      [ {E2},{E} ]; In Domain2D; Integration I1; Jacobian Jac;}
>>        }
>>   }
>> The problem is 2D. "feed" is a 1D boundary. "inc[]" is the incoming field. Domain is the union of the 2D domain (Domain2D) and the 1D domain (feed).
>>
>> The problem is that the Green's function integral E2 is evaluated once during initialization of the problem, and it is not included in the discretization
>> of the matrix. I have tried making a coupled model. This seems to be able to work, but it is not very elegant from a mathematical point of view. I have
>> come rather stuck in the problem.
>>    
>
>
> I think you should add the keyword "Dof" in the definition of the integral quantity and in the equations :
>
>    { Name form_neumann; Type FemEquation;
>      Quantity {
>        { Name E;  Type Local;     NameOfSpace scalar;}
>        { Name E2; Type Integral ; NameOfSpace scalar;
>          [ Helmholtz[]{2D,k0} * Dof{E} ];
>          In feed; Jacobian Jac ; Integration I1 ; }
>     }
>      Equation {
>        Galerkin {      [ Dof{E},{E} ]; In Domain; Integration I1; Jacobian Jac;}
>        Galerkin {      [ -inc[],{E} ]; In Domain; Integration I1; Jacobian Jac;}
>        Galerkin {      [ Dof{E2},{E} ]; In Domain2D; Integration I1; Jacobian Jac;}
>         }
>    }
>
> Let me know if it works, I'm interested.
>
> Bye,
>
> O.C.
>
>
>  
> ------------------------------------------------------------------------
>
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> http://www.geuz.org/mailman/listinfo/getdp
>  


--
Dr. Ir. Ruth V. Sabariego
University of Liege, Institut Montefiore,
Dept. of Electrical Engineering & Computer Science,
Applied & Computational Electromagnetics (ACE),
Sart Tilman Campus, Grande Traverse, 10 (B28), B-4000 LIEGE, Belgium
phone: +32-4-3663737 -- fax: +32-4-3662910 -- http://elap.montefiore.ulg.ac.be/