solving a differential equation coupling together in matrix and vector form with ode45
1 vue (au cours des 30 derniers jours)
Afficher commentaires plus anciens
I have two problem:
1) I used two functions for solving a set of equation not in matrix or vector form but like
[x(2);3+x(4)+x(3);x(4);....................]
then [t,x] = ode45(@(t,x) lili(t,x),tspan,x0);
now I need the vector of dx=[x(2) x(4) x(6)]
but it doesnt return this vector.
2) i want to solve equation like this D2y=d2x+cross(m,n)
its clear cross product is in vector form
how could i solve matrix form of differential equation?
especially initial values is a vector
1 commentaire
Torsten
le 6 Déc 2018
1) Unclear what you have done and what your problem is. Please provide the code you are using and possibly the error message you get.
2) ODE45 expects the differential equations to be given in vector format. So convert your equations from matrix form to vector form.
Best wishes
Torsten.
Réponse acceptée
roya afshar
le 7 Déc 2018
2 commentaires
Torsten
le 7 Déc 2018
You solve
x1'' = x1
x2'' = x2 + 1
x3'' = x3 + 2
with initial conditions
x1(0)=1, x2(0)=8, x3(0)=9, x1'(0)=2, x2'(0)=3, x3'(0)=4
and plot x1, x2 and x3 in plot 1 and x1', x2' and x3' in plot 2.
Is it that what you wanted to achieve ?
Plus de réponses (1)
Voir également
Catégories
En savoir plus sur Ordinary Differential Equations dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!