Matrix Dimension Must Agree

A= eye(3,3)

B= eye(6,6)

kron(A,A) resulting in 9x9 matrix, how can I change the dimension of 9x9 matrix into 6x6 matrix using voight system in matlab

Cep=k*kron(A,A)+2*M*(B-1/3*(kron(A,A))-kron(normal,normal));

Answer 1

[KALYAN ACHARJYA]

Please change in the following line, having permisible matrix dimention to works perfectly

Cep=k*kron(A,A)+2*M*(B-1/3*(kron(A,A))-kron(normal,normal)); 

Lets decompose to individual section (2nd Part with Bracket):

>> whos B
  Name      Size            Bytes  Class     Attributes
  B         6x6               288  double            

Next

>> 1/3*(kron(A,A));
>> whos ans
  Name       Size            Bytes  Class     Attributes
  ans       36x1               288  double              

Next

>> kron(normal,normal);
>> whos ans
  Name      Size            Bytes  Class     Attributes
  ans       9x9               648  double  

Lets example matrix A(6x6)-B(36x1)-C(9x9), is that permisible? To addtion or subtraction, all must have same sizes. Please check the code and modify accordingly.

:)