Is there a function to get the skew diagonal of a matrix in matlab?

2
votes
A=[a_11, a_12; a_21, a_22]

The skew diagonal is [a_12, a_21]. Right now, I flip the matrix around and use diag.

1
matlabmatrixdiagonal

1 Answers

4
votes

As an alternative to fliplr and diag, you can index directly into the matrix like this:

A = magic(3);
s = length(A);
idx = s:(s-1):(s*(s-1)+1);
%# for anti-diagonal, use the following 
%#idx = (s*(s-1)+1):(-s+1):s;

skewDiag = A(idx)
skewDiag =
     4     5     6