Question

In the M-file “matrixT.m”, i wrote the function matrixT to generate a n*3 matrix like that

function T=matrixT(alpha,n)
T=zeros(3,n);
for i=1:n
    T(1,i)=cos(alpha(i));
    T(2,i)=sin(alpha(i));
    T(3,i)=sin(alpha(i)-i*pi/2);
end

Then i use it in my main M-file

alpha=sym('alpha');
V=subs(hessian(det(matrixT(alpha,3)),alpha),alpha,alpha0);

but there are many error. Can you help me to fix this?

Answer 1

I believe your problem lies in the assignment: T(1,i)=cos(alpha(i));. You have assigned alpha to be a symbolic variable, but then you try to assign it to an array of doubles and MATLAB complains. Is it possible to evaluate the value of alpha before attempting to place it inside the array T?