Hi everyone. My name is George and i am new to matlab. I need help to complete the following code, i am stuck. Please help.

y=((-1/2)*g*t.^2)+(v*sind(x))*t

[Walter Roberson]

This appears to relate to https://www.mathworks.com/matlabcentral/answers/338404-how-can-i-solve-this-problem-please-help

Answer 1

[Walter Roberson]

Your x is length 201 or so. Your t is length 5. What size are you expecting v*sind(x))*t to be?

The * operator is algebraic matrix multiplication. In order for A*B to work, size(A,2) == size(B,1) . Your v*sind(x) is going to be about 1 x 201, and your t is 1 x 5, but 201 ~= 1

If you were to use t.' * (v*sind(x)) then that would be (1 x 5) transposed * 1 x 201, which would be 5 x 1 * 1 x 201, and that would be valid and give a 5 x 201 result. But then you would have trouble adding it to the 1 x 5 that is ((-1/2)*g*t.^2)

I suggest you consider

[X, T] = ndgrid(x, t);
y = ((-1/2)*g*T.^2) +(v*sind(X)) .* T;