How to work out the position vector?

The position vector a=[20sint;20cost;0] varies with time from t=0 to t=40 at 0.4 intervals. How do I calculate the values of a? I keep getting the message error using vertcat

Answer 1

[M]

If you define

 t=0:0.4:40;

then you have

size(sin(t))
ans =
   1   101

but 0 is a scalar of dimension 1*1

You should use

zeros(1,101);