how can i plot for loop data?

Hello everyone, I working in this heat transfer problem, but my question is about matlab code.

k=0.5; rho=2023; cv=1825; aLf=k/(rho*cv); L=0.25; nx=10; nxp=nx+1; dx=L/nx; td=12*3600; Tt=2*td;nt=60;ntp=nt+1;nTp=2*ntp;dt=td/nt; Tsd=20; Tsn=0; Ti=10; t=linspace(0,td,ntp);y=linspace(0,Tt,nTp); T1=zeros(1,ntp);T2=zeros(1,ntp); T1(1)=Ti;Tni=zeros(1,nxp); Tnii=zeros(1,nxp);

for i=1:nxp depth(i)=i*dx; for j=2:ntp time(j)= j*dt; Tx=Tsd+((Ti-Tsd)*(erf(depth(i)/(2*sqrt(aLf*(time(j))))))); T1(j)=Tx; end

subplot(223); plot(t,T1); hold on; xlabel('time (t)'); ylabel('Temperature(Tx)');grid on Tni(i)=Tx; end

time2=time; time2(1)=1;

for k=1:nxp depth(k)=k*dx; for r=1:ntp Ty=Tsn+((Tni(k)-Tsn)*(erf(depth(k)/(2*sqrt(aLf*(time2(r))))))); T2(r)=Ty; end Tnii(k)=Ty; subplot(224); plot(t,T2); hold on; xlabel('time (t)'); ylabel('Temperature(Tx)');grid on end

T=[T1,T2]; subplot(211); plot(y,T); hold on; xlabel('time (t)'); ylabel('Temperature(Tx)');grid on

my question is about the top or the first graph, its spouse to be same amount of line as in other two graph but its just drawing the last value.

can someone please help me how can i fix this, so that i can the bottom two graph into one graph.

i hope i make clear myself. Thanks in advance

Answer 1

[Star Strider]

I got all the curves to plot in the top subplot by adding matrices that stored the various values of the vectors you plot in the loops. (Before, it was only plotting the last vector of ‘T1’ and ‘T2’ calculated.) The curve in the top subplot looks a bit strange, but I’ll let you sort that, since I don’t know what you’re doing or how it should look.

I’m only listing the loops here, since those are the only changes I made:

for i=1:nxp
depth(i)=i*dx; 
for j=2:ntp 
    time(j)= j*dt;
    Tx=Tsd+((Ti-Tsd)*(erf(depth(i)/(2*sqrt(aLf*(time(j)))))));
    T1(j)=Tx;
end 

subplot(223);
plot(t,T1); hold on; xlabel('time (t)'); ylabel('Temperature(Tx)');grid on
Tni(i)=Tx;
T1M(i,:) = T1;                  % Added: Store ‘T1’ Vectors In ‘T1M’
end

time2=time;
time2(1)=1;

for k=1:nxp
depth(k)=k*dx;
for r=1:ntp
    Ty=Tsn+((Tni(k)-Tsn)*(erf(depth(k)/(2*sqrt(aLf*(time2(r)))))));
    T2(r)=Ty;
end
Tnii(k)=Ty;
subplot(224);
plot(t,T2); hold on; xlabel('time (t)'); ylabel('Temperature(Tx)');grid on
T2M(i,:) = T2;                  % Added: Store ‘T2’ Vectors In ‘T2M’
end

T=[T1M T2M];                    % Concatenate ‘T1M’ And ‘T2M’ To Form ‘T’
subplot(211);
plot(y,T); hold on; xlabel('time (t)'); ylabel('Temperature(Tx)');grid on

[Khuram]

thanks alot, actually you have solve the half of it. i think i didn't make it clear. actually the curve in the top subplot is adding the other two subplot curves into one full curve.

so the result should be something like this

[Khuram]

i solved it, so thanks alot

[Star Strider]

My pleasure!