5-FF_poisson.edp

load "iovtk"

border C(t=0,2*pi){x=2*cos(t);y=sin(t);}
mesh Th = buildmesh(C(50));
func f = x*y;
plot(Th, wait=true); // press Enter to continue

fespace Vh(Th,P1);
Vh u, v;

problem Poisson(u,v,solver=LU) =
		int2d(Th)(dx(u)*dx(v) + dy(u)*dy(v))
		- int2d(Th)(f*v)
		+ on(C, u=0);

Poisson;
plot(u, fill=true);
cout << Vh.ndof << endl;

int[int] Order = [1];
string DataName = "u";
savevtk("poisson.vtu", Th, u, dataname=DataName, order=Order);