MATLAB: Creating [-1 1] matrix given length n

Question

Hi,

I want to create N length long [-1 1] matrix,

For example: Length=2

Output:

[ 1  1
  1 -1
 -1  1
 -1 -1]

Length = 3

Output:

[ 1  1  1
  1  1 -1
  1 -1  1
 -1  1  1
   ......
 -1 -1 -1]

And so on, How can do that?

Answer 1

Hi Alice,

You can try the following:

len = 2;
N = 2^len;
bi = de2bi(N-1:-1:0);  % Convert decimal numbers in to binary
bi(bi==0) = -1; % Replace the values of 0 with -1

Hope this helps.

Regards,

Sriram