Solving System of linear equations of the Matrix of Matrices Form

2 views (last 30 days)
How can I solve this Matrix A which contains Matrices ? values can be random, I just need the method to solve for A*X = B

Answers (1)

Walter Roberson
Walter Roberson on 23 Jun 2019
You will need to write the code yourself. Mupad has no built in mathematical functions for matrices of matrices.
  2 Comments
Maria Saleem
Maria Saleem on 23 Jun 2019
Problem is , I dont know the method , using which i can solve such system of matrices
Walter Roberson
Walter Roberson on 26 Jun 2019
First you need to define what the operations even mean.
You have 2 x 2 sub-matrices. Normal linear algebra of * operator on
A11 A12 * x1
A21 A22 x2
would look like
A11*x1 + A12*x2
A21*x1 + A22*x2
Your B is 2 x 1 scalars. If x1 is n1 x m1, and x2 is n2 x m2, then we deduce that (2 x 2) * (n1 x m1) + (2 x 2) * (n2 x m2) = scalar . The * operator cannot work unless the inner dimensions match, so we deduce that n1 and n2 must be 2 -- (2 x 2) * (2 x m1) + (2 x 2) * (2 x m2) = scalar. The addition cannot work unless m1 = m2, so (2 x 2) * (2 x m) + (2 x 2) * (2 x m) = scalar. The (2 x 2) * (2 x m) is going to be 2 x m result, so you are adding a pair of 2 x m values, and the result must be 1 x 1. This is impossible in normal linear algebra. Therefore you must be using a different meaning of solving for A*X = B than standard linear algebra. You need to strictly define what your operations mean, and prove that they are consistent before you get very far.

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!