monod type equations in matlab

main.m
% Define the ODE system
function dydt = myODEs(t,y)
    % y is a vector of the dependent variables (in this case, y1 and y2)
    % t is the independent variable (time)
    dydt = [y(2); -y(1)];
end

% Set up the initial conditions and time span
y0 = [1; 0]; % initial values of y1 and y2
tspan = [0 10]; % time span to integrate over

% Solve the ODE system using ode45
[t,y] = ode45(@myODEs, tspan, y0);

% Plot the results
plot(t,y(:,1),'-',t,y(:,2),'--')
legend('y1','y2')
xlabel('Time')
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main.m
y1' = y2
y2' = -y1
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main.m
y' = [y2; -y1]
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