p.edp

来自「FreeFem++可以生成高质量的有限元网格。可以用于流体力学」· EDP 代码 · 共 37 行

verbosity=2;

mesh3 Th("dodecaedre01");
fespace Vh(Th,P23d);
func ue =   2*x*x + 3*y*y + 4*z*z + 5*x*y+6*x*z+1;
func f= -18. ;
//Vh uhe = ue; // bug ..
//cout << " uhe min:  " << uhe[]. min << " max:" << uhe[].max << endl;
/*
border cc(t=0,2*pi){x=cos(t);y=sin(t);label=1;}
mesh Th2=buildmesh(cc(50));
fespace Vh2(Th2,P2);


Vh u,v;

//uhe = ue;
macro Grad3(u) [dx(u),dy(u),dz(u)]  // EOM

problem Lap3d(u,v,solver=CG)=int3d(Th)(Grad3(v)' *Grad3(u)) - int3d(Th)(f*v) + - int3d(Th)(f*v) + on(0,1,u=ue);
Lap3d;
cout << " u min::   " << u[]. min << "  max: " << u[].max << endl;
real err= int3d(Th)( square(u-ue) );
cout << int3d(Th)(1.) << " = " << Th.mesure << endl;
Vh d= ue-u;
cout <<  " err = " << err <<  " diff l^\intfy = " << d[].linfty << endl;
Vh2 u2=u;
plot(u2,wait=1);
plot(u2,wait=1);
	{ ofstream file("dd.bb"); 
	file << "3 1 1 "<< u[].n << " 2 \n";
	int j;
	for (j=0;j<u[].n ; j++)  
	  file << d[][j] << endl; 
    }  
*/