Fastest & most effective way to create this matrix:

Question

0 个投票

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

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

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

Answer 1

Andrei Bobrov 2014-12-19

1 个投票

one way

a =[1   2   3
   4   5   6
   7   8   9];
out = kron([0 0 ; 0 1],a);

Eitan 2014-12-19

Thank you, Amazing speed!

Answer 2

Orion 2014-12-19

编辑：Orion 2014-12-19

3 个投票

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

Eitan 2014-12-19

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

Sean de Wolski 2014-12-19

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