How to copy an array with some left-over indicies also added on?

I have the following vector I would like to copy:

a = [1;2;3;4;5]

I would like my resulting vector to be

 b = [1;2;3;4;5;1;2;3;4;5;1;2;3;4;5;1;2;3]

Where it is [a] 3 times repeated, and then repeats the next 3 indicies of [a], but not the whole vector. The repmat command will not allow me to repeat it by anything other than an integer. Is there a way to specify how many more indicies I want without having to do it manually?

Thanks!

Answer 1

[Azzi Abdelmalek]

You can use repmat

a = [1;2;3;4;5]
b=[repmat(a,3,1); a(1:3)]

Answer 2

[the cyclist]

Here's one way:

b = a(mod(0:17,numel(a))+1)

Answer 3

[Fangjun Jiang]

n=3;
b=cat(1,repmat(a,n,1),a(1:n))