[Getdp] Surface charge/ normal electric field strength

Tammo Heeren Tammo.Heeren at ieee.org
Mon Oct 30 15:14:07 CET 2006


Hello Bernhard:

Thank you for your reply. I seem to have problems posting to the list, and did not expect for my message to go through. I noticed that 
when I just look at the results with the message viewer built into gmesh, I get the described behavior. However, when I call getdp from 
the console I get the expected output. I also think that the results are printed to the console during normal operation with gmesh, but 
that the output of the values (results) are not printed in the message viewer.

Tammo


> Hello!
> I tested once again with my windows machine, GetDP 1.2.1, and it seems to work here.
> However, I have to admit that on the workinghorse linux machine, there is a small glitch:
> If I pipe all output to a file (shell=bash, getdpsk is my self-compiled binary of the cvs version iirc):
> >getdpsk platehole.pro -pre all -cal -pos all &> out.txt 
> >cat out.txt
> the values are in the back of the output:
> ---------
> Operation : PostOperation 3/6
>           > 'ne.pos'
> Operation : PostOperation 4/6
> Operation : PostOperation 5/6
> Operation : PostOperation 6/6
> Resources : cpu 0.292018 s
> E n d   P o s t - P r o c e s s i n g
> E n d
> 0  2.279748153101153e-09 -2.279748153101149e-09
> 0  100 0
> 0  2.279748153101153e-11 -inf
> ----------
> Also, a while ago, while using binary mode (-bin), the screen output of simmilar numbers was _also_ binary. This tended to fill the screen with funny, but not quite helpfull ascii characters. I don't remember, but it could have occured with an older version, however it for sure was a windows machine. 
> 
> So anyway, what you could try, apart from testing with a different GetDP version, is the following:
> ---
>         Print[Q, OnRegion Grouped, Format Table, File "q.pos"];
>         Print[V, OnRegion Grouped, Format Table, File "v.pos"];
>         Print[C, OnRegion Grouped, Format Table, File "c.pos"];
> ---
> or
> ---
>         Print[Q, OnRegion Grouped, Format Table, File "dis.pos"];
>         Print[V, OnRegion Grouped, Format Table, File >"dis.pos"];
>         Print[C, OnRegion Grouped, Format Table, File >"dis.pos"];
> ---
> then by using "cat filename.pos" (linux) or "type filename.pos" (windows) you hopefully will get the following three lines:
> --
> 0  2.279748153101153e-09 -2.279748153101149e-09
> 0  100 0
> 0  2.279748153101153e-11 -inf
> --
> 
> nice greetings from Vienna, and good luck,
> bernhard
> 
> 
> -----Ursprüngliche Nachricht-----
> Von: getdp-bounces at geuz.org [mailto:getdp-bounces at geuz.org] Im Auftrag von Tammo Heeren
> Gesendet: Donnerstag, 26. Oktober 2006 17:08
> An: getdp at geuz.org
> Betreff: Re: [Getdp] Surface charge/ normal electric field strength
> 
> 
> I have been trying to recreate the given problem and I found a somewhat
> strange behavior.
> As the postprocessing and postoperation I have:
> 
> PostProcessing {
> { Name all; NameOfFormulation for_v;
>  Quantity {
> { Name v ;
>  Value {
>  Local { [ {v} ] ; In Vol ; Jacobian Vol; }
>  }
> }
> { Name e ;
>  Value {
> Local { [ {d v} ] ; In Vol ; Jacobian Vol; }
>  }
> }
> { Name ne ;
>  Value {
> Local { [ Norm[{d v}] ] ; In Vol; Jacobian Vol; }
>  }
> }
> { Name Q ; Value { Term { [ {Q} ] ; In Grouped ; } } }
> { Name V ; Value { Term { [ {V} ] ; In Grouped ; } } }
> { Name C ; Value { Term { [ {Q}/{V} ] ; In Grouped ; } } }
>  }
> }
> }
> 
> PostOperation {
> { Name all ; NameOfPostProcessing all;
>  Operation {
> Print[ v, OnElementsOf Vol, File "v.pos" ] ;
> Print[ e, OnElementsOf Vol, File "e.pos" ] ;
> Print[ne, OnElementsOf Vol, File "ne.pos" ] ;
> Print[ Q, OnRegion Grouped, Format Table] ;
> Print[ V, OnRegion Grouped, Format Table] ;
> Print[ C, OnRegion Grouped, Format Table] ;
>  }
> }
> }
> 
> Which is essentially what is given in the wiki. However, my getdp output is:
> 
> GetDP : Loading : Processing data 'Y:\captest1.res'
> GetDP : Info : Selected PostProcessing 'all'
> GetDP : Info : Selected Mesh 'Y:\captest1.msh'
> GetDP : Operation : PostOperation 1/6
> GetDP : > 'Y:\v.pos'
> GetDP : Info : Generate ExtendedGroup '_BF_Entity_9'
> (GroupsOfNodesOf)
> Info : Parsing file 'Y:\v.pos'
> Info : Parsed file 'Y:\v.pos'
> GetDP : Operation : PostOperation 2/6
> GetDP : > 'Y:\e.pos'
> Info : Parsing file 'Y:\e.pos'
> Info : Parsed file 'Y:\e.pos'
> GetDP : Operation : PostOperation 3/6
> GetDP : > 'Y:\ne.pos'
> Info : Parsing file 'Y:\ne.pos'
> Info : Parsed file 'Y:\ne.pos'
> GetDP : Operation : PostOperation 4/6
> GetDP : Operation : PostOperation 5/6
> GetDP : Operation : PostOperation 6/6
> GetDP : Resources : cpu 0.296875 s
> GetDP : E n d P o s t - P r o c e s s i n g
> GetDP : E n d
> 
> No results are shown for PostOperation 4-6, and also no error message.
> Everything else seems to work just fine. Anybody have any idea?
> 
> Tammo
> 
> 
> On 17 Oct 2006 at 16:55, Kubicek Bernhard wrote:
> 
> > Hello Tammo,
> > I tried to put together a nice example for capacity calculations in the Wiki just about 10 minutes ago.
> > Hopefully this can help you with your goals.
> >
> > If there are no glitches, maybe somebody else would like to add them
> > to the frontpage. At the moment the example is hiding here:
> >
> > http://www.geuz.org/getdp/wiki/Capacitor2D
> >
> > Nice greetings,
> > Bernhard Kubicek
> >
> > freelancer for Arenal Research, Vienna, Austria
> >
> > -----Ursprüngliche Nachricht-----
> > Von: getdp-bounces at geuz.org [mailto:getdp-bounces at geuz.org] Im Auftrag von Tammo Heeren
> > Gesendet: Montag, 9. Oktober 2006 22:34
> > An: getdp at geuz.org
> > Betreff: [Getdp] Surface charge/ normal electric field strength
> >
> >
> > How do I extract the surface charge density or the electric field
> > normal to the
> > surface from the solution I optained with getdp and gmsh. The surfaces are
> > defined in gmsh a physical lines. My eventual goal is to compute the
> > capacitance of this (and other geometries). Any suggestions?
> >
> > Tammo