From: Bastien R. <rou...@gm...> - 2008-02-25 12:57:42
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Le dimanche 24 février 2008, Fredy konig a écrit : > Hi Bastien, Please do not top post. > ideally the EM sim should include FEM, MoM and FDTD, and mixed version > but we need to start with one at a time and the FEM seems to be the one > the most documented (on open source) I wish to have more time and > concentrate on all of them but I also have a day job to do. Ok I understand that you have day jobs activity and even private life :-) But I have some problem with your approach. Do you want to create a EM field simulator or create bridge between program? BTW about FEM I will recommand you to read (very pedagogical and conscern all the different methods): @Book{ numerical-sadiku:2000, title = "Numerical techniques in electromagnetics", author = "Matthew N.~O. Sadiku", year = "2000", edition = "2", isbn = "0-8493-1395-3", address = "Boca Raton", publisher = PUB_CRC, lang = "langenglish" } and one of the last review on the method by ITOH: @Article{ fembibliography-coccioli:1996, title = "Finite-element methods in microwaves: a selected bibliography", author = "R. Coccioli and T. Itoh and G. Pelosi and P.~P. Silvester", journal = IEEE_M_AP, year = "1996", volume = "38", number = "6", pages = "34--48", month = dec, doi = "10.1109/74.556518", ISSN = IEEE_M_AP, publisher = PUB_IEEE, lang = "langenglish", url = "http://ingfi9.die.unifi.it/femcorner/map/cont2_1.htm" } Reading your blog you seems to not understand that is FEM. I quote your blog: > The FEM can be used to calculate the field inside a space. > > but first you need to define: > the boundary conditions which will helps to resolve the unknown element of > the differential solution. the mesh structure (or sometimes called I am sorry but fields does not exist without boundary condition. Maxwell equation are not single valued (ie it exist one and only one solution) without boundary condition. BTW you forget to mention that you need to specify characteristic of volume (epsilon_r, mu_r, rho_r...) > triangulation) of studied surface or volume.(Series of triangle for 2D > meshing or series of tetrahehra or pyranids for 3D meshing) Yes like FDTM :-) triangulation of volume is the same for FDTM and FEM, boudary triangulation for the MOM. For me FEM is a varitionnal method for solving partial differential equation. Do not take it as a personnal attack but you are in a world where each word and word order is important. > And don't worry I ll speak my mind on here. > The idea with the blog is that it may bring more people to the project by > spreading the word. Like some IT guys whose still believe in the power of > the great MS as their jobs still depend on it, they told me that I m a kind > of open source evangelist ... :-) I thought i was funny ) as I was showing > them alternative open source software > > but when I have the opportunity I spread the good words of Qucs. > > Ideally I ll submit a programming tutorial for EM coding on qucs doc later > once I understood how to use the proper lib and combining it in qucs. I am doing EM work everyday and I do not know why you say you want to join qucs. qucs is based on model, EM field simulator is exact. I am ok you are filling a gap, but it is another project that you are creating. > About git, I m sorry but I still don't see any benefit, > I think now the best options would be to keep it under the Qucs > repository. git is better than cvs. everybody know cvs is crappy. May be you do not believe me, perhaps you will believe linus torvald and Andrew Tridgell. The key word for git is decentralisation.Another good thing is atomic commit. And BTW git is pretty easy to learn http://www.kernel.org/pub/software/scm/git/docs/tutorial.html And I will ease the development for external reviewer. Last word I use git daily for the component lib on tux famiily: http://git.tuxfamily.org/qcomponents/qucscomponents.git BTW on tux family you could have a true mediawiki as home page that is really useful for brain storming. > Thanks > Fredy > > > Message du 21/02/08 à 15h41 > > De : "Bastien ROUCARIES" <rou...@gm...> > > A : fre...@vo... > > Copie à : quc...@li..., "dany" <da...@gm...> > > Objet : Re: [Qucs-devel] About the EM simulator > > > > Le jeudi 21 février 2008, Fredy konig a écrit : > > > Hi all, > > > > > > I will go quiet and concentrate on getFEM and MEEP for some time. > > > > You could add for solver; > > SUPER LU (BSD) includig MPI > > http://crd.lbl.gov/~xiaoye/SuperLU/ > > UMFPACK (mono) > > http://www.cise.ufl.edu/research/sparse/umfpack/ > > > > > I summarised my goal for the EM simulator in my blog. > > > http://emctheory.blogspot.com/ > > > > Please comment her and send your mind by mail. > > > > I do not think for instance that FEM is the best solution. For radiation > > stuff MOM or hybrid is better. > > > > BTW nec is not Mom it is a hybrid code based on MoM > > > > Code aster and fenic project have not yet a EM solver > > > > > > For git use tuxfamily. please do not use svn. BTW tuxfamily is better > > managed than source forge. You are freer. I could open a project on > > tuxfamily in less than ten minutes. > > > > Regards > > > > Bastien > > > > > I ll keep you posted when I ll get some good results. > > > regards > > > Fredy > > > > > > > Message du 16/02/08 à 22h45 > > > > De : "Bastien ROUCARIES" <rou...@gm...> > > > > A : quc...@li..., fre...@vo... > > > > Copie à : "dany" <da...@gm...> > > > > Objet : Re: [Qucs-devel] About the EM simulator > > > > > > > > Le samedi 16 février 2008, Fredy konig a écrit : > > > > > Hi all, > > > > > > > > > > I agree with you about doing things in an organised manner. Before > > > > > I start planning the work I would like to ask few questions: > > > > > > > > > > First we should decide which road to take Qt3 or Qt4 > > > > > I am myself a supporter of using qt4, as I already start to play > > > > > with it but it may not be the best option. Gopala, Stefan, Bastien > > > > > and other qucser may think otherwise, please let me know. Qt3 may > > > > > be easier for a start? but Qt4 may be best for the future of the > > > > > project? 1) is it better to start on Qt4? or Qt3? do both would be > > > > > time consuming? is there plan to release soon a stable qt4 version > > > > > of qucs? > > > > > > > > No need to use graphical stuff. The worst and harder thing to get > > > > right is the core not the graphical stuff. It will be the last thing > > > > what you will do! > > > > > > > > BTW Personnally I prefer to code my geometry, and not draw it. For > > > > instance I prefer to type I want a sphere radius 1 center 0,0,0, than > > > > drawing it. And I am not alone. > > > > > > > > I think something like a povray like syntax will be really good > > > > suited. Why not reusing kpovmodeler and use special instruction for > > > > EM property ? > > > > > > > > > Second, if we use Qt4 the first way to make executable is with > > > > > Qmake and make. or the autoconfig/automake used in the current > > > > > version. but I read Gopala input about Cmake, I also read some nice > > > > > thing about Cmake on a linux journal saying that it is the way > > > > > forward but never try. 2)CMake ? would it be a good way forward > > > > > when using Qt4? > > > > > > > > Idem. Keep a good insulation between graphical stuff and core. > > > > For the core autoconf/automake is the way to do. > > > > > > > > And BTW use modern development tool like git for creating the > > > > project. > > > > > > > > > Third, looking at the code of qucs I can see that there is > > > > > differrent source diretories defining specific block for > > > > > qucs-attenuattor , qucs-filter, etc... 3)should we add an qucs-ems > > > > > (electromagnetic simulator) directory and start this as a single > > > > > block.?is there any restriction or rule to follow to be compatible > > > > > with the rest of qucs.? > > > > > > > > No need tobe compatible. Respect the unix philosphy one program, one > > > > task. We could always create translator program. > > > > > > > > > Forth, About the display of EM output we will probably have to use > > > > > the openGL libraries 4) Is anybody know where to find good Qt4 > > > > > openGL examples? > > > > > > > > Do not waste your time with gui at this time of project, please. We > > > > could use something like paraview > > > > http://www.paraview.org/New/index.html. > > > > > > > > Qt support is directly included and it is well suported by big > > > > science project. It is in the way to be debianized :-) > > > > > > > > > Fith, about the EM engine we need to select the computing method > > > > > TLM, FEM , FDTD, MoMs etc... I suggested to start with c++lib such > > > > > as nec++ using MoM, other possibilities are YATPAC lib in c using > > > > > TLM etc... 5)This will need to be discuss more, and I will try to > > > > > combine all suggestions? but ideas are welcome. > > > > > > > > MoM like in momentum is a best thing to do. Nec++ is a good starting > > > > point but code does not include (to my best knowledge) planar circuit > > > > computation.It will be good to do that. I strongly think we need to > > > > develop moment solution. > > > > > > > > About FEM, I know some free tool. I expect a lot about fenic project. > > > > > > > > http://home.gna.org/getfem/ > > > > http://www.fenics.org/wiki/FEniCS_Project > > > > > > > > FTDT package exist use MEEP > > > > http://ab-initio.mit.edu/wiki/index.php/Meep > > > > > > > > > 6)Should we also plan for parallel computing like they do on > > > > > commercial package? I am not sure what open source lib are > > > > > available for this.. > > > > > > > > They exist package what could work. Some of the guys in the uni > > > > building next to me have coded mumps. > > > > http://mumps.enseeiht.fr/. It work well and is public domain. > > > > Packaging could be hard, but I could try to get some contact with the > > > > authors. > > > > > > > > BTW if we could use this kind of stuff for qucs it will be good :-) > > > > > > > > > 7)Finally one important step is to collect related imformation, > > > > > papers or related project. if you send me your idea I try to > > > > > publish it in coordinated manner. > > > > > > > > I can also publish some paper. I have the chance to have direct > > > > access to some fellow members. But I will prefer to wait and see. > > > > About paper I can also collect. > > > > > > > > Regards Bastien > > > > > > > > > Thanks all > > > > > and please be patient as it is a big task. > > > > > Fredy > > > > > > > > > > > Message du 15/02/08 à 19h21 > > > > > > De : "dany" <da...@gm...> > > > > > > A : quc...@li... > > > > > > Copie à : > > > > > > Objet : [Qucs-devel] About the EM simulator > > > > > > > > > > > > Hi > > > > > > > > > > > > My name is Dany and I've been playing around with qucs quite some > > > > > > time now. I decided that I want to help push this project > > > > > > forward. > > > > > > > > > > > > Specifically I'm interested in the EM simulator, the challenge > > > > > > looks interesting. > > > > > > > > > > > > Markus, Fredy, I'm ready to start on your cue. Do you have > > > > > > something already? Or is it necessary to start from scratch? > > > > > > In any case, I think we should try and do it in an organized > > > > > > manner, meaning, first to draw an outline of what needs to be > > > > > > done, and not go all rogue programming :) > > > > > > > > > > > > Looking forward to hearing from you soon, > > > > > > Dany > > > > > > > > > > > > ----------------------------------------------------------------- > > > > > >---- ---- This SF.net email is sponsored by: Microsoft > > > > > > Defy all challenges. Microsoft(R) Visual Studio 2008. > > > > > > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > > > > > _______________________________________________ > > > > > > Qucs-devel mailing list > > > > > > Quc...@li... > > > > > > https://lists.sourceforge.net/lists/listinfo/qucs-devel > > > > > > > > > > Fredy Konig > > > > > > > > > > > > > > > > > > > > ------------------------------------------------------------------- > > > > >---- -- This SF.net email is sponsored by: Microsoft > > > > > Defy all challenges. Microsoft(R) Visual Studio 2008. > > > > > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > > > > _______________________________________________ > > > > > Qucs-devel mailing list > > > > > Quc...@li... > > > > > https://lists.sourceforge.net/lists/listinfo/qucs-devel > > > > > > > > -- > > > > > > > > "ROUCARIES Bastien" > > > > > > > > rou...@gm... > > > > --------------------------------------------------------------------- > > > >---- ------ DO NOT WRITE TO rou...@gm... OR > > > > BE BLACKLISTED > > > > > > Fredy Konig > > > > -- > > > > "ROUCARIES Bastien" > > > > rou...@gm... > > ------------------------------------------------------------------------- > >------ DO NOT WRITE TO rou...@gm... OR BE > > BLACKLISTED > > Fredy Konig -- "ROUCARIES Bastien" rou...@gm... ------------------------------------------------------------------------------- DO NOT WRITE TO rou...@gm... OR BE BLACKLISTED |