MATLAB: Busy- Message solving 1st order ODE

Hi Experts, I am new in Mathlab, and i have come across "busy" on the status bar when trying to solve simultaneous 1st order ODE. My questions are is mathlab taking time to compute or i have made an error on the code. Since i am a beginner, please simplify your response. Anyhelp is greatly appreciated. Thanks and below is the code: M-file
function dcdt= CELLULOSE(t,c)
%c(1)=c(A), c(2)=c(B), c(3)=c(C), c(4)=c(D), c(5)=c(E), c(6)=c(F), c(7)=c(G),
%c(8)=c(H), c(9)=c(I), c(10)=c(J), c(11)=c(K), c(12)=c(L), c(13)=c(M)
global K1 K2 K3 K4 TEMP R
dcdt=[-c(1)*(K1+K4); K1*c(1)-c(2)*(K2+K3); 0.95*K2*c(2); 0.25*K2*c(2); 0.20*K2*c(2);0.20*K2*c(2);0.25*K2*c(2); 0.20*K2*c(2);0.15*K2*c(2);0.1*K2*c(2);0.9*K2*c(2);0.65*K2*c(2);K3*c(2)];
Call Function:
>> clear all
>> global K1 K2 K3 K4 TEMP R
>> TEMP = 1000;
>> R=8.3141;
>> K1=(8*10^18)*exp(-46000/(R*TEMP));
>> K2=(1*10^9)*exp(-30000/(R*TEMP));
>> K3=(9.99*10^12)*exp(-10000/(R*TEMP));
>> K4=(8.10*10^7)*exp(-32000/(R*TEMP));
>> tspan =[0:400];
>> c0=[1 0 0 0 0 0 0 0 0 0 0 0 0]
c0 =
       1     0     0     0     0     0     0     0     0     0     0     0     0
>> [t,x]=ode45('CELL',tspan,c0);
Please help! please

Best Answer

It is recommended that you do not use "global". The alternative is http://www.mathworks.com/help/techdoc/math/bsgprpq-5.html
To get a better idea of what is going on in your routine, use odeset() to create an options structure that you pass to ode45. In particular you could ask for Stats http://www.mathworks.com/help/techdoc/ref/odeset.html#f92-1016858
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