On Mon, Feb 09, 2009 at 02:24:46PM +0000, A Navaei wrote: > > > > You should be able to just link against DOLFIN. All the information > > you need is provided by pkg-config: > > > > pkg-config --cflags dolfin > > pkg-config --libs dolfin > > Is this approach platform-independent or are there solutions for other > platforms?
Yes, pkg-config works on many platforms.
> >> Once this is
> >> compiled as a python module, you can have something like
> >>
> >> f = itk.ImageToDolfinFunction("dolfin.jpg")
> >>
> >> as you mentioned previously. Obviously, it you want to call this from
> >> c++ you will need linking to both libraries again. It would be helpful
> >> if you could have a look at my dofmap question.
> >
> > I'm not very keen on using it from C++, but if you want to initialize
> > a function in C++, you need to have a function space.
>
> Me neither, but there is no choice: we need a way for data conversion
> without going through numpy everytime.
>
> > The simplest way
> > would be to create a very simple form file and then compile it with
> > FFC (using -l dolfin). For example
> >
> > element = FiniteElement("Lagrange", "triangle", 1)
> > v = TestFunction(element)
> > u = TrialFunction(element)
> > a = v*u*dx
> >
> > If you store this in say a file named "P12D.form" you can then use the
> > generated class named
> >
> > P12DFunctionSpace
>
> I would like the user to have the option of specifying the finite
> element corresponded to the image function space. Is there a more
> dynamic way of doing this? I guess the following would work if we can
> assign the right signature for dofmap, it hides Mesh and DofMap
> dependencies in the cunstructor:
>
>
> class ImageFunctionSpace : public FunctionSpace
> {
> public:
> ImageFunctionSpace(const ImageType* & imageData, const FiniteElement&
> element)
> {
> PixelType * buffer = const_cast<PixelType *>
> (imageData->GetBufferPointer()); // imageData is an itk image type
> instance
> m_ImageData = (double *) (buffer);
>
> m_ImageSize = image->GetBufferedRegion().GetSize();
>
> dolfin::Mesh mesh;
> if(ImageDimension == 2)
> {
> mesh = UnitSquare(m_ImageSize[0], m_ImageSize[1]);
> }
> else if(ImageDimension == 3)
> {
> mesh = UnitCube(m_ImageSize[0], m_ImageSize[1],
> m_ImageSize[2]);
> }
>
> dolfin::DofMap dofmap("?", mesh); // <-- what's the right
> signature?
>
> FunctionSpace(mesh, element, dofmap);
> };
>
> void eval(double* values, const double* x, const Function& v) const;
> {
> if(ImageDimension == 2)
> {
> int i = int((m_ImageSize[0] - 1) * x[0]);
> int j = int((m_ImageSize[1] - 1) * x[1]);
> int index = i + (m_ImageSize[0] * j);
> values[0] = m_ImageData[index];
> }
> else if(ImageDimension == 3)
> {
> int i = int((m_ImageSize[0] - 1) * x[0]);
> int j = int((m_ImageSize[1] - 1) * x[1]);
> int k = int((m_ImageSize[2] - 1) * x[2]);
> int index = i + (m_ImageSize[0] * j) + (m_ImageSize[0]
> * m_ImageSize[1] * k);
> values[0] = m_ImageData[index];
> }
> }
>
> protected:
> double *m_ImageData;
> int[ImageDimension] m_ImageSize;
> };
Try looking at the functions
ElementLibrary::create_finite_element(std::string signature);
ElementLibrary::create_dof_map(std::string signature);
They are defined in dolfin/elements/ElementLibrary.h/cpp.
--
Anders
signature.asc
Description: Digital signature
_______________________________________________ DOLFIN-dev mailing list [email protected] http://www.fenics.org/mailman/listinfo/dolfin-dev
