How to sort even and odds elements in an array or vector recursively?

Hi,

I am trying to sort an array of 1xN in different odd and even arrays till the length last array =4 for example: X=1:32; N=length(X) m=log2(N);

for i=1:m

A=X(1,1:2:end); %for odd bits B=X(1,2:2:end); %for even bits X=A;

if l=4 break end

a=B(1,1:2:end); %for odd bits b=B(1,2:2:end); %for even bits B=a; end

i m getting output for X=1:16 but if I increase length of X to N then its is not working; for X=1:32, I am getting only odd values

i want the o/p as [1 9 17 25 5 13 21 29 3 11 19 27 7 15 23 31 2 10 18 26 6 14 22 30 4 12 20 28 8 16 24 32]

In my code it is considering odd bits only. I want to do this for N bit but my loop is not working in that case. Please help me out

Thanks in advance

Answer 1

[Julia]

Hi,

I don't really get your intention. What are A, B, a and b for?

And where do you compute l for the if-statement?

It would be helpful if you edited your code.

[sachin gawande]

Actually I am trying t store array in A and B

here is my code for 16 bits but I want to generalize it for N bits, in this code if i put X =1:32 i am getting only odd integers in fact I want all integers.

clc clear all X=[1:16];

N=length(X); m=log2(N)

for i=1:m

    A=X(1,1:2:end) % for odd bits
    B=X(1,2:2:end)% for even bits
    X=A;  

    l=length (X);
    if l==4 
    break
    end

    a=B(1,1:2:end) % for odd bits
    b=B(1,2:2:end)% for even bits
    B=a;   
end
[A B a b]

u can try this code you will understand what exactly A B a b are?

[Julia]

I think I know what the problem is.

For

X = 1:16

You compute A ans B twice but a and b only once, so you keep your even values in a and b.

But for

X = 1:32

you compute A, B, a and b twice. The second time you compute a and b you use B, which now contains only odd values --> a and b now contain only odd values.

B=a

is overwritten in the next loop iteration by

B=X(1,2:2:end)