block diagonal matrix in the opposite diagonal

Is there any function/way to construct a matrix with block matrcies in the opposite diagonal. I know of blkdiag( ) but it gives a matrix with blocks in the main diagonal

Answer 1

[Paul]

Here's one option

a = rand(2);
b = rand(2,3);
A = blkdiag(a,b)

A = 4×5

0.0976 0.7033 0 0 0 0.6779 0.8610 0 0 0 0 0 0.4852 0.7807 0.6937 0 0 0.5431 0.4091 0.2433

D = oppblkdiag(a,b)

D = 4×5

0 0 0 0.0976 0.7033 0 0 0 0.6779 0.8610 0.4852 0.7807 0.6937 0 0 0.5431 0.4091 0.2433 0 0

function D = oppblkdiag(varargin)

c = cellfun(@(x) fliplr(x),varargin,'UniformOutput',false);
D = fliplr(blkdiag(c{:}));

end

[John D'Errico]

Exactly.

[Romio]

Thanks. I think it should be implemeted as built in function in matlab