MATLAB: Create matrix with double rows of [-1 1]

Question

Hey guys, I want to create a matrix which looks the following:

-1  0  0  0
 1  0  0  0
 0 -1  0  0
 0  1  0  0
 0  0 -1  0
 0  0  1  0
 0  0  0 -1
 0  0  0  1

and so on. Does anyone know a good way to do that? Maybe there is a helpful command for that 🙂

Thanks a lot 🙂

Oh, sorry, an edit:

I would also have an even more complex matrix, which would look the following…

   0  0  0  0
  -1  0  0  0
   0  1  0  0
   0 -2  0  0
   0  0  2  0
   0  0 -3  0
   0  0  0  3
   0  0  0 -4

Any suggestions? 🙂

Answer 1

Simple answer:

clear all
clc
A = zeros(8,4)
for i =2:2:size(A,1)
    A(i-1,i/2) = (i/2)-1;
    A(i,i/2) = -i/2;
end
A
A =
       0     0     0     0
      -1     0     0     0
       0     1     0     0
       0    -2     0     0
       0     0     2     0
       0     0    -3     0
       0     0     0     3
       0     0     0    -4

There is probably a more compact way to do it though :)