matlab code solves the system of differential equations but it plots the initial values,not the answer.help!!please!!

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hi everyone!i have this code and it runs but there is a problem,it keeps the initial values instead of solving the differential equations can you help? :)
function my_ode
[T,F]=ode15s(@diff2,[0 5],[10 20 0 333]);
plot(T,F(:,1),'-',T,F(:,2),'.',T,F(:,3),'*',T,F(:,4),'^')
end
function df=diff2(t,f)
Tc=60+5*(60-25);
nw=20;
k0=5e10;
x=15000;
c=-9020;
pa=14.384;
pw=55.382;
pb=13.668;
cpa=125;
cpw=75;
cpb=250;
a=-55570;
b=-349700;
df=zeros(4,1);
df(1)=-k0*exp(c/f(4))*f(1);
df(2)=0;
df(3)=-df(1);
df(4)=(x*(Tc-f(4))-df(1)*a-df(3)*b-(df(1)*cpa+df(3)*cpb+df(2)*cpw)*f(4))/(f(1)*cpa+f(3)*cpb+f(2)*cpw);
end
  1 Comment
Geoff Hayes
Geoff Hayes on 31 Oct 2015
Maroubi - please clarify what the problem is. In your question title you state ...it plots the initial values,not the answer and in your question body you state ...it keeps the initial values instead of solving the differential equations. Have you stepped through the code to verify that T and F are correct? It does seem that (over time) the problem converges to a solution.

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