Compose two vectors from one vector with step

Hi, I have vector S=[1:64]. I want to compose two vectors:

S_1=[ 1 2 3 4 9 10 11 12 17 18 19 20 ....], step of M=4

S_2=[5 6 7 8 13 14 15 16 21 22 23 24....], step of M=4

L=length(S)

length(S_1)=length(S_2)=L/2

[yousef Yousef]

S = 1:64;

xx = reshape(x, 4, 16);

xxx=xx(:,1:2:end)

xxxx=xx(:,2:2:end-1)

S_1=xxx(:)'

S_2=xxxx(:)'

This answer does what I want. However Im sure there is a way to answer this question in a shorter code, any advice? Thank you

Answer 1

[Voss]

N = 64;
S = 1:N;
M = 4;

S_new = reshape(permute(reshape(S,M,2,[]),[1 3 2]),N/2,[]).'

S_new = 2×32

1 2 3 4 9 10 11 12 17 18 19 20 25 26 27 28 33 34 35 36 41 42 43 44 49 50 51 52 57 58 5 6 7 8 13 14 15 16 21 22 23 24 29 30 31 32 37 38 39 40 45 46 47 48 53 54 55 56 61 62

Now S_new(1,:) is your S_1 and S_new(2,:) is your S_2.

[yousef Yousef]

Perfect. Appreciated it

Thank you

[yousef Yousef]

I just have one more question. I'm a modelling transmitter and receiver. This work is needed to be done at the transmitter. I want to have the original signal at the receiver. I mean reconstruct S back. Any idea? Thank you

[Voss]

S_reconstructed = reshape(permute(reshape(S_new.',M,[],2),[1 3 2]),1,[])

[yousef Yousef]

Perfect. Appreciated. Thank you

[Voss]

You're welcome!