dolfin team mailing list archive

[A Navaei <axnavaei@xxxxxxxxxxxxxx>]

2009/2/17 A Navaei <axnavaei@xxxxxxxxxxxxxx>:
> The following minimal test for Function in c++ reveals some bugs. I
> guess this example can help me with dealing with the current issues of
> ImageFunction.
>
> (1) interpolate.py does not work when a Function is created in c++ and
> wrapped (see comment [2]). It seems that the bug is originated from
> the copy constructor (see comment [3])
>
> (2) In order to perform the interpolation, why is it necessary to
> create another Function and then copy it?
>
> (3) Signature checkes seem not working properly (see comment [1]). The
> signature-based assignments are error-prone anyway, why the
> object-oriented approach is not used?
>
>
I'm adding another issue:

(4) Sub-classing Function and calling the sub-class interpolate()
function does not call eval().

Code is attached.


-Ali

#include <dolfin/function/Function.h>
#include <dolfin/function/FunctionSpace.h>
#include <dolfin/mesh/Mesh.h>
#include <dolfin/fem/FiniteElement.h>
#include <dolfin/fem/DofMap.h>
#include <dolfin/mesh/UnitSquare.h>

#include <boost/shared_ptr.hpp>

using namespace dolfin;

int msize[2];

class MyFunction : public Function
{
public:
	MyFunction(const FunctionSpace& V) : Function(V) {};
			
	void eval(double* values, const double* x) const
	{
		int i = int((msize[0] - 1) * x[0]);
		int j = int((msize[1] - 1) * x[1]);
		int index = i + (msize[0] * j);
		std::cout << "\tEvaluating [" << i << ", " << j << "](" << index << ")" << std::endl;
	}
};

int main() 
{
	typedef boost::shared_ptr< const Mesh > MeshConstPointerType;
	typedef boost::shared_ptr< const FiniteElement > ElementConstPointerType;
	typedef boost::shared_ptr< const DofMap > DofMapConstPointerType;
	
	std::cout << "- Creating mesh...";
	msize[0] = 10; msize[1] = 10;
	UnitSquare mesh(msize[0] - 1, msize[1] - 1);
	std::cout << "done." << std::endl;
	
	std::string elemSig("FiniteElement('Lagrange', 'triangle', 1)");
//	std::string elemSig("dummy"); // [1] This gives segmentation fault.
	std::string dofSig("FFC dof map for FiniteElement('Lagrange', 'triangle', 1)");
	
	std::cout << "- Creating FunctionSpace...";
	FunctionSpace V(MeshConstPointerType(&mesh, NoDeleter<const dolfin::Mesh>()),
				ElementConstPointerType(new dolfin::FiniteElement(elemSig)),
				DofMapConstPointerType(new dolfin::DofMap(dofSig, mesh)));
	std::cout << "done." << std::endl;
			
	std::cout << "- Creating Function...";
	MyFunction v(V);
	std::cout << "done." << std::endl;
	
/*	
	// [2] This gives segmentation fault.
	std::cout << "- Interpolating as interpolate.py...";
	Function Pv(v); // [3] The copy ctor doesn't work.
	v.interpolate(Pv.vector(), v.function_space());
	std::cout << "done." << std::endl;
*/	
	// [4] This seems to work fine.
	std::cout << "- Interpolating...";
	v.interpolate(v.vector(), v.function_space());
	std::cout << "done." << std::endl;
};