Index exceeds the number of elements (1)

close all;
dt = 0.01;%time step

k1=1;
m=1;%initial parameters
u1 =2;
u2 =1;
v1=2;
a1=1;

tend=10;

t=0;
i=1

while t < tend-2*dt
    v1h=v1(i)-dt*k1*u1(i)-u2(i)/ (2*m);
    u1(i+1)= u1(i)+ dt*v1h;
    a1(i+1)= -k1*u1(i+1)/2;
    v1(i+1)= v1h + dt*a1(i+1)/2;
    i = i+1;
    t = t + dt
end

plot(linspace(0,tend,tend/dt),u1);

Answer 1

[Adam Danz]

On the second iteration of your while-loop, u2(i) is causing the error since you're trying to access the second element of u2 but u2 will always be u2=1 and that never changes in your code. I see you're updating u1 within the while loop but that isn't happening for u2.