clear;
//coeficientes
TD = 10;
TE = 40;
TINI = 25;
L=1;
alpha = 40*10^-6;
celulas = 200;
dt = 0.1;
dx = L/celulas;
S = (alpha*dt)/(dx*dx);
B=0.7;
Tnova(1) = TE;
Tnova(celulas) = TD;
Tvelha(1)= TE;
Tvelha(celulas)= TD;
t=0;
tmax=10000000;
totalit=0;
itmax=10000
tolerancia=0.000001;

for i=2:(celulas-1)
    Tnova(i)=TINI;
    Tvelha(i)=TINI;
end;

while(t<tmax)
    while (totalit<itmax)
        erro=-1;
        for i=2:(celulas-1)
            Taux=(Tvelha(i)+S*(1-B)*(Tvelha(i-1)-2*Tvelha(i)+Tvelha(i+1))+S*B*Tnova(i-1)+S*B*Tnova(i+1))/(1+2*S*B);
            //disp(Taux)
            erro=max(erro,abs(Taux-Tnova(i)));
            Tnova(i) = Taux;
        end;
        if (erro<tolerancia) then
            break;
        end;
    totalit=totalit+1;
end;
   Tvelha= Tnova;
   t=t+dt;
end;

for i=1:celulas
    barra(i)=i;
end
//disp(barra)
//disp(Tnova);
plot (barra,Tnova)