Ho to repeat a vector?

Hi all,

Could anybody plz be a help me what is the build-in function for:

repvec (1:5, 2)

which results in:

ans = 1 1 2 2 3 3 4 4 5 5

Thank you so much for your help :)

[Jordan Lessentier]

https://fr.mathworks.com/help/matlab/ref/repelem.html

Answer 1

[Matt Fig]

vec = 1:5;
reshape(vec([1 1],:),1,[])
% Or reshape(vec(ones(1,N),:),1,[]) to expand N times

For more complex expansions, give this file a try: EXPAND

Answer 2

[Image Analyst]

If you have the Image Processing Toolbox, you can do it this way

out = imresize(a, [1 10], 'nearest')

where a is your 1:5 vector, and the 10 is how long you want the output to be.

[Jan]

+1: While this is not very efficient, it is a creative recycling of the Signal Processing toolbox.

Answer 3

[Azzi Abdelmalek]

vec=1:5
out=[vec;vec];
out=out(:)'

If you want to repeat n times

vec=1:5
n=10;
out=repmat(vec,n,1);
out=out(:)';

Answer 4

[Jan]

While I'd prefer Matt Fig's approach in real programs, here another approach, which might be interesting:

vec    = 1:5;
n      = 2;
index  = zeros(1, length(vec) * n);
index(1:n:end) = 1;
index  = cumsum(index);
result = vec(index);