Как, используя цикл, создать систему уравнений

for I,J,K,L=1:6
C(I,J,K,L)=sum (i,j,k,l=1:6) D(I,i)*D(J,i)*D(K,k)*D(L,l)*C(I,j,k,l)
end

D [3,1]=0, D [3,3]=1,  D [1,1]=cos phi

I, j,k,l,...=1,2,3.

C'=D*C

C'=(C[IJKLMNPQ]); C=(C[ijklmnpq])

D

D[1,1]=cos phi, D[1,2]=sin phi, D[2,1]=-sin phi, D[2,2]=cos phi, D[3,1]=D[3,2]=0, D[3,3]=1

C[ijklmnpq]=C[mnpqijkl]

I,J,K,L,M,N,P,Q,i,j,k,l,m,n,p,q

D=D(I,i)*D(J,j)*D(K,k)*D(L,l)*D(M,m)*D(N,n)*D(P,p)*D(Q,q)

C'=D*C

syms y y1 y2 y3 x x1 x2 x3 
syms a a11 a12 a13 a21 a22 a23 a31 a32 a33 
 
x=[x1
    x2
    x3];
y=[y1
    y2
    y3];
a=[a11 a12 a13
    a21 a22 a23
    a31 a32 a33];
y=a*x
 
y = 
 a11*x1 + a12*x2 + a13*x3
 a21*x1 + a22*x2 + a23*x3
 a31*x1 + a32*x2 + a33*x3

syms y y1 y2 y3 x x1 x2 x3 
syms a a11 a12 a13 a21 a22 a23 a31 a32 a33 
 
n=3
for i=1:n
    for j=1:n
        y(i)=(a(i,j)*x(j))
    end
end
print(y)

C'(IJKLMNPQ), C(ijklmnpq)

D(I,i)*D(J,j)*D(K,k)*D(L,l)*D(M,m)*D(N,n)*D(P,p)*D(Q,q)

D(1,1)=cos(x); 
D(1,2)=sin(x); 
D(1,3)=0; 
D(2,1)=-sin(x); 
D(2,2)=cos(x); 
D(2,3)=0 ;
D(3,1)=0 ;
D(3,2)=0 ;
D(3,3)=1;

C'(IJKLMNPQ)=(D(I,i)*D(J,j)*D(K,k)*D(L,l)*D(M,m)*D(N,n)*D(P,p)*D(Q,q))*C(ijklmnpq)

i,j,k,l,m,n,p,q

d=[cos(x) sin(x) 0 -sin(x) cos(x) 0 0 0 1];
[DI,DJ,DK,DL,DM,DN,DP,DQ]=ndgrid(d);
D=DI.*DJ.*DK.*DL.*DM.*DN.*DP.*DQ;

C, C'

C(1,1,1,1,1,1,1,1), C(1,1,1,1,1,1,1,2), C(1,1,1,1,1,1,2,2), ... C(3,3,3,3,3,3,3,3),
C'(1,1,1,1,1,1,1,1), C'(1,1,1,1,1,1,1,2), C'(1,1,1,1,1,1,2,2), ... C'(3,3,3,3,3,3,3,3)[/