i suppose the problem lies not in VTKFile.cpp. you consider a tensor function to have a rank >= 2, but for my tensor function the rank returned by e.g.
e.function_space().element().value_rank() is 1. So it is rather a vector with 4 components having rank 1. possibly value_rank() in the FiniteElement class should return 2 even for a 2d tensor function, then your code in VTKFile is fine, but i didn't look into the FiniteElement classes. patrick -------- Original Message -------- Subject: Re: [FEniCS-users] [Fwd: Re: tensor function] Date: Wed, 30 Sep 2009 11:30:45 +0200 From: Patrick Riesen <prie...@student.ethz.ch> CC: fenics <fenics-us...@fenics.org> References: <4ac31db1.2040...@student.ethz.ch> <4ac320f4.1000...@student.ethz.ch> <4ac32181.8050...@cam.ac.uk> seems that the tensor function for a 2d problem doesn't get to the output structure for a tensor function but to that for a vector function because it only has rank = 1. the write out for tensor is only invoked for a (3x3) tensor with rank = 2. Garth N. Wells wrote: > > > Patrick Riesen wrote: >> Hello, >> >> I don't know if this is a problem (dolfin0.9.2): >> When i was writing the TensorFunction e to a vtk-file after a solve >> by just using >> >> file << e >> >> the results i got were absolutely nonsense. I got three components, >> but none of them made any sense. This is why i was thinking i'm doing >> something completely wrong in my equations/code, >> > > VTK output of tensor functions is untested. I would be very surprised if > it did work. Dig around in VTKFile.cpp to see if you can find the problem. > > Garth > >> But if i first separate all components and write them to separate >> files as >> Function e11 = e[0]; >> Function e12 = e[1]; >> Function e21 = e[2]; >> Function e22 = e[3]; >> >> fileE11 << e11; >> fileE12 << e12; >> fileE21 << e21; >> fileE22 << e22; >> >> the solutions look reasonable (uff!..) and e12 and e21 are the same. >> >> regards, >> patrick >> >> >> Patrick Riesen wrote: >>> sorry, something went wrong, this would be the message: >>> >>> -------- Original Message -------- >>> Subject: Re: [FEniCS-users] tensor function >>> Date: Wed, 30 Sep 2009 10:52:02 +0200 >>> From: Patrick Riesen <prie...@student.ethz.ch> >>> To: Anders Logg <l...@simula.no> >>> References: <4ac0a8d5.6040...@student.ethz.ch> >>> <20090928122033.gh2...@olorin> <4ac0ad56.50...@student.ethz.ch> >>> <20090928140134.ga24...@olorin> <4ac0c346.7020...@student.ethz.ch> >>> >>> or maybe not.. >>> >>> i can not do >>> >>> Function e11 = e[0][0]; >>> >>> i get >>> >>> error: no match for 'operator[]' in >>> 'dolfin::Function::operator[](dolfin::uint)(0u)[0]' >>> >>> >>> but i can get components doing >>> >>> e11 = e[0]; >>> e12 = e[1]; >>> e21 = e[2]; >>> e22 = e[3]; >>> >>> >>> i suppose for dolfin 0.9.3 it is the case as described below and for >>> dolfin 0.9.2 the case as above therefore ? >>> (which is what i am still using currently) >>> >>> greetings, >>> patrick >>> >>> Patrick Riesen wrote: >>>> this helped to sort things out, thanks again. >>>> patrick >>>> >>>> Anders Logg wrote: >>>>> On Mon, Sep 28, 2009 at 02:34:30PM +0200, Patrick Riesen wrote: >>>>>> Hi, >>>>>> >>>>>> thans for the quick response, >>>>>> >>>>>> therefore when V is the function space of the (e, v, p) element and >>>>>> >>>>>>> e[0] = (a, b) >>>>>>> e[1] = (c, d) >>>>>>> e[0][0] = a >>>>>>> e[0][1] = b >>>>>>> e[1][0] = c >>>>>>> e[1][1] = d >>>>>> therefore doing >>>>>> >>>>>> fs = new SubSpace(V,0,0) >>>>>> >>>>>> corresponds to the subspace for the two components (a, b) of the >>>>>> element and not just for a, which then would be SubSpace(V,0,0,0) ? >>>>> Yes. >>>>> >>>>> -- >>>>> Anders >>>> _______________________________________________ >>>> FEniCS-users mailing list >>>> fenics-us...@fenics.org >>>> http://fenics.org/mailman/listinfo/fenics-users >>> >>> _______________________________________________ >>> FEniCS-users mailing list >>> fenics-us...@fenics.org >>> http://fenics.org/mailman/listinfo/fenics-users >> >> _______________________________________________ >> FEniCS-users mailing list >> fenics-us...@fenics.org >> http://fenics.org/mailman/listinfo/fenics-users > > _______________________________________________ FEniCS-users mailing list fenics-us...@fenics.org http://fenics.org/mailman/listinfo/fenics-users _______________________________________________ DOLFIN-dev mailing list DOLFIN-dev@fenics.org http://www.fenics.org/mailman/listinfo/dolfin-dev
