how to create 2X10000 matrix using for loop in matlab

I am trying to create a matrix of size 2X10000 using for loop ie If

X={x1 x2 x3 x4 x5 x6 x7 x8 x9 x10............}

them my

tX1=[x1 -x2* x3 -x4* x5 -x6* ...........]   row 1 from matrix in for loop
tX2=[x2 x1* x4 x3* x6 x5* ...........] row 2 from matrix in for loop

[Pratik Bajaria]

Could you please elaborate the question..?

Answer 1

[Image Analyst]

Seems pretty easy, assuming * means complex conjugate. Did you try anything like this

for k = 1 : 2 : length(X)-1
  tX1(k) = X(k);
  tX1(k+1) = -conj(X(k+1)); % Negative complex conjugate.
  tX2(k) = X(k+1);
  tX2(k+1) = conj(X(k));
end

Answer 2

[dpb]

Given an x vector of length 20003,

X=[x(1) -x(2:2:end-2).*x(3:2:end-1); ...
   x(2)  x(1:2:end-3).*x(4:2:end)]

Answer 3

[Andrei Bobrov]

x0 = reshape(X,2,[]);
x1 = [x0(1,:);-conj(x0(2,:))];
x2 = [x0(2,:);conj(x0(1,:))];
tX = [x1(:).';x2(:).'];

[Kishore]

Thank u andrei bobrov this block should work within for loop ie i need to convert 1XN matrix to 2XN matrix using for loop