Convenient matrix building functions are|
For example, zeros(m,n) produces an m × n matrix of zeros and zeros(n) produces an n × n one; if A is a matrix, then zeros(A) produces a matrix of zeros of the same size as A.
If x is a vector, diag(x) is the diagonal matrix with
x down the diagonal; if A is a square matrix:
A = 1 2 3 4 5 6 7 8 9then diag(A) is a vector consisting of the diagonal of A. What is diag(diag(A))? Try it.
Matrices can be built from blocks. For example, if A is a 3-by-3 matrix, then
B = [A, zeros(3,2); ones(2,3), eye(2)]will build a certain 5-by-5 matrix. Try it!