Output of the solution of a assigned point

General Discussion
5

Dear Professor,

According to your suggestion, I have added “-pc_type lu” in the set of sparams. However, the solutions with time iteration is still wrong.
The parallel computing code is as follows,
"…
…
fespace Vh(Th,Pk);
Vh [u,uB,uC], [v,vB,vC],[u1f,u2f,u3f]=[.0,.0,.0],[u1b,u2b,u3b]=[.0,.0,.0];
…
varf Lame([u,uB,uC],[v,vB,vC])
=int3d(Th)(densityidt2uv)-int3d(Th)(density2idt2u1fv)+int3d(Th)(densityidt2u1bv)+
int3d(Th)(densityidt2uBvB)-int3d(Th)(density2idt2u2fvB)+int3d(Th)(densityidt2u2bvB)+
int3d(Th)(densityidt2uCvC)-int3d(Th)(density2idt2u3fvC)+int3d(Th)(densityidt2u3bvC)+
int3d(Th)(lambdadiv(u,uB,uC)div(v,vB,vC)+2.mu( epsilon(u,uB,uC)'epsilon(v,vB,vC)))
+ on(1001,u=0.,uB=0.,uC=0.00001(1.-2.(pif*(t-tt))^2)exp(-(pif*(t-tt))^2))
+on(2001,2002,2003,2004,2005,2006,2007,u=0.,uB=0.,uC=0.);

[u1b,u2b,u3b]=[0.,0.,0.];
[u1f,u2f,u3f]=[u1b,u2b,u3b];
[u,uB,uC]=[u1f,u2f,u3f];

Mat A;
createMat(Th, A, Pk)

for(int i=0;i<100;++i) {
t=t+dt;

matrix Loc = Lame(Vh, Vh,tgv=-1); //solve the problem
real[int] rhs = Lame(0, Vh,tgv=-1);
set(A, sparams = “-ksp_view -ksp_max_it 100 -pc_type lu”);
Vh def(u); // local solution
A = Loc;
u = A^-1 * rhs;

macro def1(u)u// EOM

//Time iteration of displacement
[u1b,u2b,u3b]=[u1f,u2f,u3f];
[u1f,u2f,u3f]=[u,uB,uC];

macro params()cmm = “Global solution time=”+t, fill = 1// EOM
plotMPI(Th, def1(u), P1, def1, real, params)

int[int] Order=[1,1];
savevtk(“uhydrate6_y.vtu”, Th,[u,uB,uC], dataname=“[u,uB,uC]”, order=Order,append = true);
}."
The obtained solution significantly monotonically increases with number of iterations from (negative solution)^20 to (positive solution)^20. Such solution is apparently wrong. Because the solution should be fluctuating around 0, the solution has been obtained from serial calculation code using FreeFem++.

Please give me some advice. Thank you very much.

Best regards,
Liu