Define the ODE equals the matrix. Runge Kutta 4

6 次查看（过去 30 天）
Phong Pham
Phong Pham 2012-8-7
I have velocity vector in matrix form [ 1, 2, 3,4 ];
Velocity is dx/dt 1) first matlab function f = func(t,x)
f= [1,2,3,4]
2) Second matlab
dt=0.001;
t=[0:dt:20];
xinital= [ 0 0 -2 0.4]
use the Runge Kutta to estimate the final x
for i = 1: 20/dt
k1 = dt*func(t(i),x(i));
k2 = dt*func(t(i)+dt/2,x(i)+dt*k1/2);
k3 = dt*func(t(i)+dt/2,x(i)+dt*k2/2);
k4 = dt*func(t(i)+dt,x(i)+dt*k3);
x(2,:) =xintial(1,:) + (k1 + 2*k2 + 2*k3 + k4)/6;
end
I keep getting error message dimension mismatch on xinitial.
Please help

请先登录，再回答此问题。

采纳的回答

Babak
Babak 2012-8-7
Change
xinital= [ 0 0 -2 0.4]
to
xinital= [ 0 0 -2 0.4]'
or
xinital= [ 0;0;-2;0.4]

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Numerical Integration and Differential Equations 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by