MATLAB: How do you circshift progressive rows an increasing amount

Question

If I have a matrix:

[nan nan nan nan nan]

[ 1a nan nan nan nan]

[ 1b 2b nan nan nan]

[ 1c 2c 3c nan nan]

[ 1d 2d 3d 4d nan]

I want to change it to this:

[ 1a 2b 3c 4d nan]

[ 1b 2c 3d nan nan]

[ 1c 2d nan nan nan]

[ 1d nan nan nan nan]

[nan nan nan nan nan]

I tried:

for K = 1:length(A)

A = circshift(A(:,K),K);

Thank you.

Answer 1

You need to index a column in A in your output as well.

for K = 1:size(A,2)
   A(:,K) = circshift(A(:,K),K);
end

If you want to move every NaN to the bottom, you can also use the sort function.