# MATLAB: Saving values with variables in a matix

matrixsymbolicSymbolic Math Toolboxvariables

Hi all
I not really into Matlab, so ther might some mistakes in my code that are easy to solve.
that is my code so far
nodes=2H_d=ones(nodes,nodes)for N=1:nodes    for M=1:nodes        syms omega         Pos=sym('pos',[1 nodes]);        P=sym('p',[1 nodes]);                H_d=(1/2*P(N)^2+omega^2*Pos(M)^                2)    endend
My problem is that I want an Matix H_d that is 2×2 large and consists of the values 'calculated' in the for loop.
These are the values created bey the loop, with the variables inside.
H_d = (omega^2*pos1^2)/2 + p1^2/2  H_d = (omega^2*pos2^2)/2 + p1^2/2  H_d = (omega^2*pos1^2)/2 + p2^2/2  H_d = (omega^2*pos2^2)/2 + p2^2/2
Now I'd like to put all these values in a Matix, like:
H_d=[(omega^2*pos1^2)/2+p1^2/2    (omega^2*pos2^2)/2+p1^2/2     (omega^2*pos1^2)/2+p2^2/2    (omega^2*pos2^2)/2+p2^2/2] 
usually then I had thath problem I just changed H_d to H_d(N,M) and then I get I matrix with all values.
But that didn't work here.
     The following error occurred converting from sym to double:Error using symengine (line 58)DOUBLE cannot convert the input expression into a double array.If the input expression contains a symbolic variable, use VPA.Error in split_Hamiltonians_diagonalisation (line 16)        H_d(P(N),Pos(M))=(1/2*(P(N)^2+omega^2*Pos(M)^2));        
• nodes=2;syms omega Pos=sym('pos',[1 nodes]);P=sym('p',[1 nodes]);       H_d=sym(ones(nodes,nodes)); % if your creating a square matrix it can also be written as sym(ones(noses)) for N=1:nodes    for M=1:nodes        H_d(N,M)=(1/2*P(N)^2+omega^2*Pos(M)^2);    endend