Solving a system of ODEs in MATLAB

I'm trying to solve two ODEs in MATLAB. I wrote this function, but I keep getting an error message.

function dy = diff_eqs(y,t)

%Constants R = 100; k12 = 33; k21= 33; V1 =10; V2 = 25; k2=8;

%Equations dy = zeros(2,1);

dy(1,1) = (R - k12.*y(1) + k21 .* y(2))./V1;

dy(2,1) = (k12.*y(1) - k21.* y(2) - k2.*y(2))./V2;

end

After I get this down, I plan on using ode45 to solve.

[Jan]

With a standard formatting your question would look nicer.

Whenever your write "I get an error message" in a forum, it is a good idea to post a copy of it. Matlab's error messages are such useful that it is worth to read them.

Answer 1

[Azzi Abdelmalek]

function dy = diff_eqs(t,y)
dy=zeros(2,1);
R=100;
k12=33; 
k21=33;
V1=10; 
V2=25;
k2=8;
dy(1) = (R - k12*y(1) + k21*y(2))/V1;
dy(2) = (k12*y(1)-k21*y(2)-k2*y(2))/V2;

%call the function

x0=[0;0];
[t,y]=ode45(@diff_eqs,[0 10],x0)

[Azzi Abdelmalek]

it's diff_eqs(t,y) not diff_eqs(y,t)