BLOCK_MATRIX _ _ _ _ _ _ _ _ _ _ _ _ operator
<r>,<c> :- positive integers.
<matrix\_list> :- a list of matrices.
block_matrixcreates a matrix that consists of <r> by <c> matrices filled from the <matrix\_list> row wise.
B := make_identity(2); [1 0] b := [ ] [0 1] C := mat((5),(5)); [5] c := [ ] [5] D := mat((22,33),(44,55)); [22 33] d := [ ] [44 55] block_matrix(2,3,{B,C,D,D,C,B}); [1 0 5 22 33] [ ] [0 1 5 44 55] [ ] [22 33 5 1 0 ] [ ] [44 55 5 0 1 ]