Solving 3rd order ODE
3 visualizaciones (últimos 30 días)
Mostrar comentarios más antiguos
Kevin Tran
el 10 de Mayo de 2020
Comentada: Star Strider
el 11 de Mayo de 2020
Hi guys, I need to solve this 3rd order ODE:
?⃛+2??̈+3??̇+4??=2, t≥0, ?̈(0)=?̇(0)=?(0)=0
This is my script:
[t,y] = ode45(@diffeq3,[0 50],[0;-1;1]);
plot(t,y)
function dy = diffeq3(t,y)
if t >= 0
dy(3) = 0
dy(2) = 0
dy(1) = 0
end
dy = zeros(3,1);
dy(1) = y(2);
dy(2) = y(3);
dy(3) = 2 - 2*y(3) - 3*y(2) - 4*y(1);
end
Did I do it right?
I got two questions, I got three curves which on is which?
And did I define t≥0, ?̈(0)=?̇(0)=?(0)=0 correct? With:
if t >= 0
dy(3) = 0
dy(2) = 0
dy(1) = 0
Thanks in advance for the help!
0 comentarios
Respuesta aceptada
Star Strider
el 10 de Mayo de 2020
There appears to be a factor of ‘y(1)’ missing in the last 3 terms of the ‘dy(3)’ equation. (I gave your differential equation as posted to the odeToVectorField function to be certain.)
Also, the if block is not necessary. It does nothing, and produces slower code.
6 comentarios
Más respuestas (0)
Ver también
Categorías
Más información sobre Ordinary Differential Equations en Help Center y File Exchange.
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!