Fastest & most effective way to create this matrix:

Hey there, I have been searching for hours for a good solution & not found one yet. I need to create this matrix (6X6):

A =    0 0 0 0 0 0  
   0 0 0 0 0 0 
   0 0 0 0 0 0
     0 0 0 1 2 3
   0 0 0 4 5 6
   0 0 0 7 8 9

It must be in an effective & short way. Thank you if anyone can help with this one.

Answer 1

[Andrei Bobrov]

one way

a =[1   2   3
   4   5   6
   7   8   9];

out = kron([0 0 ; 0 1],a);

[Eitan]

Thank you, Amazing speed!

Answer 2

[Orion]

clear A;
A(4:6,4:6) = reshape(1:9,3,3)'

[Eitan]

Thank you! I actually used that code because it looks shorter. you guys are great!

[Sean de Wolski]

I'd expect this to be the fastest way to do this.