ODE45 mesh grid

Suppose I want to solve

f = @(t,x) [-x(1)*x(2);x(1)*x(2)-x(2);x(2)]
[t,xa]=ode45(f,[0 6], [4 0.1 0]);

Now I want to present t like

t=0:0.001:6

How can I do this?

[alpedhuez]

https://stackoverflow.com/questions/2549238/how-do-i-force-ode45-to-take-steps-of-exactly-0-01-on-the-t-axis

Answer 1

[Star Strider]

Use your ‘t’ vector as the ‘tspan’ argument:

f = @(t,x) [-x(1)*x(2);x(1)*x(2)-x(2);x(2)];
t=0:0.001:6;
[t,xa]=ode45(f,t, [4 0.1 0]);

figure
plot(t, xa)
grid
legend('x_1', 'x_2', 'x_3')

.