Changing matrices form, echelon the matrices

Question

tevzia 2014-1-14

编辑： Azzi Abdelmalek 2014-1-14

Hello,

I have a matrices that i want to change the form/type of it. My array is lik that

    A  B  C  D
  A 0  1  0  0
  B 0  0  1  1
  C 0  0  0  1
  D 0  0  0  0

And i want to change this matrices like this:

A, A, 0
A, B, 1
A, C, 0
A, D, 0
B, C, 1
B, D, 1
C, D, 0

Or like this;

A, A, 0
A, B, 1
A, C, 0
A, D, 0
B, A, 0
B, B, 0
B, C, 1
B, D, 1
C, A, 0
C, B, 0
C, C, 0
C, D, 1
D, A, 0
D, B, 0
D, C, 0
D, D, 0

I would appreciate if you show me how to change it.

Thanks

Answer 1

Azzi Abdelmalek 2014-1-14

编辑：Azzi Abdelmalek 2014-1-14

A=[0  1  0  0
0  1  1
0  0  1
0  0  0]

%For the first case

n=size(A,1)
out=[A(1,:)';cell2mat(arrayfun(@(x) A(x,x+1:n)',(2:n-1)','un',0))]

% Forthe second case

B=A';
B=B(:)