Re: How to multiply between column in the matrix

On 11/15/2012 11:29 PM, Idra wrote:
> I have this matrix:
>
> dFF2=ff2n(4)
>
>
> dFF2 =
>
> 0 0 0 0
> 0 0 0 1
> 0 0 1 0
> 0 0 1 1
> 0 1 0 0
> 0 1 0 1
> 0 1 1 0
> 0 1 1 1
> 1 0 0 0
> 1 0 0 1
> 1 0 1 0
> 1 0 1 1
> 1 1 0 0
> 1 1 0 1
> 1 1 1 0
> 1 1 1 1
>
> Let: column 1 =A1,column 2=A2, column 3=A3 and column 4=A4
>
> I want to produce a matrix with
>
> [A1 A2 A3 A4 A1A2 A1A3 A1A4 A2A3 A2A4 ...A3A4...A1A2A3 A1A2A4 A2A3A4 ...A1A2A3A4]
>
> it is a 16x12 matrix..Ouch, how to do that?
>


Let A be your matrix above...

--------------------
  B = zeros(size(A,1),14);
  k = 0;
  
  for i = 1:4
      I = nchoosek(1:4,i);

      for j = 1:size(I,1)
          k = k+1;
          B(:,k) = prod(A(:,I(j,:)),2);
      end

  end
--------------------

--Nasser
--Nasser