copy and add elements and expand array

Hello everyone. I have a question.

I have an array which has 500 elements such as A = [1,2,3,4,5,6,7...500]

And I want to copy last values of the each dual arrays and add them after dual arrays like that --> B = [1,2,2,3,4,4,5,6,6,7,8,8,.....,500]

How can I do this?

Thanks..

Answer 1

[madhan ravi]

A=1:500;
B=zeros(1,numel(A)+floor(numel(A)/2));
B(3:3:end)=A(2:2:end);
B(setdiff(1:numel(B),3:3:end))=A

[OKG]

great! Thank you!

[KALYAN ACHARJYA]

+1 Great