On Thursday 18 December 2008 06:22:40 Evan Lezar wrote: > On Thu, Dec 18, 2008 at 7:00 AM, Johan Hake <[email protected]> wrote: > > On Wednesday 17 December 2008 22:21:06 Anders Logg wrote: > > > On Wed, Dec 17, 2008 at 09:06:55PM +0100, Johan Hake wrote: > > > > On Wednesday 17 December 2008 20:41:24 DOLFIN wrote: > > > > > One or more new changesets pushed to the primary dolfin repository. > > > > > A short summary of the last three changesets is included below. > > > > > > > > > > changeset: 5405:96d1443b6830dda228122b9dcd34d52f38906598 > > > > > tag: tip > > > > > user: Anders Logg <[email protected]> > > > > > date: Wed Dec 17 20:41:16 2008 +0100 > > > > > files: TODO demo/pde/waveguide/cpp/Forms.form > > > > > demo/pde/waveguide/cpp/main.cpp demo/pde/waveguide/python/demo.py > > > > > description: > > > > > Get waveguide demo running. Results in Python and C++ differ. > > > > Strange. > > > > > > Try a recompile of the cpp demo. It worked for me :P > > > > > > > > Johan > > > > > > Not for me. > > > > > > With C++, I get > > > > > > Cutoff frequency = 7.02634 > > > > > > and with Python, I get > > > > > > Cutoff frequency: 7.04491466139 > > > > Same here! First I got 40. something in the C++ demo, and when I then > > after a > > recompile got 7.0 something I wrongly assumed that they were the same... > > I just checked and the previous versions of the demo (pre FunctionSpace) > also do not give identical results. > (c++: 7.02634315, python: 7.04491469, analytical: 7.024814731). > > It seems as if the difference is due to the rectangular mesh being uses. > In the python demo, the mesh is set to a right diagonal, whereas in the c++ > demo the default (crisscross) is used. > > Removing the last parameter of the Rectangle constructor or setting it to 2 > in the python demo confirms this as the result is then identical to that of > the c++ one. This also explains why the c++ result is more accurate since > there are more (smaller) elements in the crisscross mesh.
I did not know about this feature! Thanks for the report. The demo is fixed now. Johan _______________________________________________ DOLFIN-dev mailing list [email protected] http://www.fenics.org/mailman/listinfo/dolfin-dev
