Undefine variable 't'

I do not know at which point I make mistake.

function dydt = comb(t,y)
R = 8314.510; % J/kmol.K
Cp = 1200; % J/kg.K
h_F = 4e7; % J/kg
Po = 2545284; % Pa
To = 753; % K
Fo = Po/(17*R*To);
Oxo = 16*Po/(17*R*To);
Pro = 0;
dydt = [-h_F*(-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))/(Cp*Po/(R*y(1)));...
     (-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))-(y(2)*(-h_F*(-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))/(Cp*Po/(R*y(1))))/y(1));...
     16*((-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))-(y(2)*(-h_F*(-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))/(Cp*Po/(R*y(1))))/y(1)));...
     -17*((-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))-(y(2)*(-h_F*(-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))/(Cp*Po/(R*y(1))))/y(1)))]
[t,y]= ode15s(@comb, [0 0.004],[300;Po/(17*R*To);16*Po/(17*R*To);0]);
plot(t,y(:,1),'-o');
title('Temperature vs time');
xlabel('Time, t [s]');
ylabel('Temperature, T[K]');
end

Answer 1

[madhan ravi]

R = 8314.510; % J/kmol.K
Cp = 1200; % J/kg.K
h_F = 4e7; % J/kg
Po = 2545284; % Pa
To = 753; % K
Fo = Po/(17*R*To);
Oxo = 16*Po/(17*R*To);
Pro = 0;

[t,y]= ode15s(@comb, [0 0.004],[300;Po/(17*R*To);16*Po/(17*R*To);0]);   %function calling ourside the function definition
plot(t,y(:,1),'-o');
title('Temperature vs time');
xlabel('Time, t [s]');
ylabel('Temperature, T[K]');

function dydt = comb(t,y)
R = 8314.510; % J/kmol.K
Cp = 1200; % J/kg.K
h_F = 4e7; % J/kg
Po = 2545284; % Pa
To = 753; % K
Fo = Po/(17*R*To);
Oxo = 16*Po/(17*R*To);
Pro = 0;
dydt = [-h_F*(-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))/(Cp*Po/(R*y(1)));...
     (-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))-(y(2)*(-h_F*(-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))/(Cp*Po/(R*y(1))))/y(1));...
     16*((-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))-(y(2)*(-h_F*(-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))/(Cp*Po/(R*y(1))))/y(1)));...
     -17*((-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))-(y(2)*(-h_F*(-6.19e9*exp(-15098/y(1))*(y(2)^0.1)*((0.21*y(3))^1.65))/(Cp*Po/(R*y(1))))/y(1)))]
end

[NURUL FARINA BINTI MAZLAN]

Do I need to write it in separate script?

[madhan ravi]

just copy everything and save it as a script file

[NURUL FARINA BINTI MAZLAN]

It works. Thanks!

[madhan ravi]

Anytime :)