void TypeOfFE_P1Lagrange1d::FB(const What_d whatd,const Mesh & ,const Element & K,const R1 & P,RNMK_ & val) const
{
// const Triangle & K(FE.T);
R l[]={1.-P.sum(),P.x};
assert(val.N() >=Element::nv);
assert(val.M()==1 );
val=0;
RN_ f0(val('.',0,op_id));
if (whatd & Fop_D0)
{
f0[0] = l[0];
f0[1] = l[1];
}
if (whatd & Fop_D1)
{
R1 Dl[3];
K.Gradlambda(Dl);
if (whatd & Fop_dx)
{
RN_ f0x(val('.',0,op_dx));
f0x[0] = Dl[0].x;
f0x[1] = Dl[1].x;
}
}
}
void TypeOfFE_P2Lagrange1d::FB(const What_d whatd,const Mesh & ,const Element & K,const R1 & P,RNMK_ & val) const
{
// const Triangle & K(FE.T);
R l[]={1.-P.sum(),P.x};
assert(val.N() >=E::nv+E::ne);
assert(val.M()==1 );
val=0;
RN_ f0(val('.',0,op_id));
//
if (whatd & Fop_D0)
{
int k=0;
for(int i=0;i<E::nv;++i)
f0[k++] = l[i]*(2*l[i]-1.);
for(int i=0;i<E::ne;++i)
f0[k++] = 4.*l[E::nvedge[i][0]]*l[E::nvedge[i][1]];
}
if (whatd & (Fop_D1|Fop_D2))
{
R1 Dl[2];
R l4[2]={ (4*l[0]-1),(4*l[1]-1)};
K.Gradlambda(Dl);
RN_ f0x(val('.',0,op_dx));
int k=0;
for(int i=0;i<E::nv;++i,++k)
{
f0x[k] = Dl[i].x*l4[i];
}
for(int i=0;i<E::ne;++i,++k)
{
int i0=E::nvedge[i][0],i1=E::nvedge[i][1];
f0x[k] = 4*(Dl[i1].x*l[i0] + Dl[i0].x*l[i1]) ;
}
assert(k==1);
//cout << " D2 " << whatd << endl;
if (whatd & Fop_D2)
{
//cout << " D2 " << endl;
RN_ f0xx(val('.',0,op_dxx));
k=0;
for(int i=0;i<E::nv;++i,++k)
{
f0xx[k] = 4.*Dl[i].x*Dl[i].x;
}
for(int i=0;i<E::ne;++i,++k)
{
int i0=E::nvedge[i][0],i1=E::nvedge[i][1];
f0xx[k] = 8.*Dl[i0].x*Dl[i1].x;
}
}
}
}
