La fonction main() appelle 3 fonctions pour
void main()
{
Grid g;
g.rectInit(15,15); // triangulates the unit square with a 15x15 grid
g.prepgrid(); // computes areas of triangles, neighbor points...
Vector<vectNB> f(g.nv), sol(g.nv); //rhs of -Delta(sol)=f=1, sol=0 on bdy
for(int i=0;i< g.nv;i++) f[i] = 1 ;
Bandmatrix<matNB,vectNB> aa(nv,g.bdth);
buildmatlaplace(g,aa);
for(int i=0;i< g.nv;i++)if(g.v[i].where) aa(i,i)= 1e10; // p=1e10
sol = rhs(g,f); // computes right hand side of linear system
cout<< "pivot=" << gaussband(aa,sol,1) << endl;
}