Plot several solution curves to y'(t) = y(t) - t

Hi!

I want to plot several solution curves to an ODE using ode45. My main problem is that I do not understand how to write y(t) - t.

The whole equation is as following:

y'(t) = y(t) - y, 0 <= t <= 2, with the initial conditions y(0) E [-2, 2].

I have tried solving it by using syms y(t) without any success...

Best regards

Answer 1

[Sam Chak]

Hi @Carla Roos

You can create an anonymous function of t and y.

fun = @(t, y) y - t;        % <--- Type like this

% solve for y(0) = 2
[t, y] = ode45(fun, [0 2], 2);
plot(t, y), hold on

% solve for y(0) = -2
[t, y] = ode45(fun, [0 2], -2);
plot(t, y), hold off, 

grid on, xlabel('t'), ylabel('y(t)'),
legend('y(0) = 2', 'y(0) = –2')

[Carla Roos]

Thank you very much!

Hope you have a great day! :)