How to minimize a vector using a vector input?

Hi everyone, below there is my function whose output needs to be minimized. This function accepts as input a vector h which is used to evaulate the matrix Twan (Temperature Wall Analytical). Then, the square differences between two matrix is evaluated. So, I need to minimize the vector f using the vector h! Could you help me? Thanks a lot!

function f=thetamethodfun2D(h)

global L Grid beta frames b p Taw Ti Twsp phi phitrue dt k Tamb dx T_new_b cont

% h=x; sigma=5.67e-8; eps=0.91;

%% % Modifica matrice Laplaciano

for i=1:b-2 par=k/(2*dx) * 1/( -3*k/(2*dx) - h(i+1) ); L(i,i)= L(i,i)+ (-4)*par;

    L(i+(b-2),i)=L(i+(b-2),i) + par;
end

I=speye(size(L)); A=I-beta*L;

%% Ciclo temporale

Tan_matr2=Ti; Tan_vet_old2=Tan_matr2(Grid>0);

for it=1:frames

    %%%Effetto Boundary conditions
    T_new_b(:,1)=(sigma*eps)./(( -3*k/(2*dx) - h(:) )).* (Twsp(:,it).^4 - Tamb^4) - h(:)*Taw./(( -3*k/(2*dx) - h(:) ));
    T_bordo2=4*del2(T_new_b,dx);

    T_b2=T_bordo2(Grid>0);

    Tan_vet_new2=A\(Tan_vet_old2) + A\(beta*dx*dx*T_b2); 

    Tan_matr2=T_new_b;
    Tan_matr2(Grid>0)=Tan_vet_new2;
            % Per neumann (derivata al primo ordine)
    Tan_matr2(1,2:end)=Tan_matr2(2,2:end);
    Tan_matr2(end,2:end)=Tan_matr2(end-1,2:end);

    Tan_matr2(:,1)= (Tan_matr2(:,3) - 4*Tan_matr2(:,2)).*(k/(2*dx) .* 1./( -3*k/(2*dx) - h(:) )) + Tan_matr2(:,1);

    %%%%
    Twan(:,it)=Tan_matr2(:,1);

    % Aggiornamento
    Tan_vet_old2 =Tan_vet_new2;

end

f=sum((Twan'-Twsp').^2);

cont=cont+1;

% if cont==b % keyboard % cont=0; % end end