How to repeat different vectors to form another vector?

Hi I would like to construct a vector as:

1,2,3,1,2,3,1,2,3,4,5,6,4,5,6,4,5,6.....k-2,k-1,k,k-2,k-1,k

i.e. repeat [1,2,3], [4,5,6].... 3 times. How to do this without a for loop?

Thank you very much.

Answer 1

[Fangjun Jiang]

repmat()

[Fangjun Jiang]

%%
k=5;
a=1:k*3;
b=reshape(a,3,[]);
c=repmat(b,3,1);
d=c(:)'

[xiaojuezi]

Thank you very much!

Answer 2

[Sudheer Bhimireddy]

For OPs example, it would be:

>> A = [repmat([1,2,3],1,3) repmat([4,5,6],1,3)] %... repmat([k-2,k,k],1,3)];
>> A =

     1     2     3     1     2     3     1     2     3     4     5     6     4     5     6     4     5     6