Problem 2585. How to reverse spdiags?
The spdiags function extracts all nonzero diagonals from the m-by-n matrix A.
So if
A = [1 2 3;4 5 6;7 8 9]
then
spdiags(A) = [7 4 1 0 0;
0 8 5 2 0;
0 0 9 6 3]
But if I give you spdiags(A), can you give me A ?
Solution Stats
Problem Comments
-
1 Comment
Paul Berglund
on 5 Oct 2014
% this problem is not guaranteed solvable
isequal(spdiags([eye(5) zeros(5)]),spdiags(eye(5)))
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