Cody

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Problem 2585. How to reverse spdiags ?

Created by Jean-Marie Sainthillier

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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],

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 ?

Solve

Solution Stats

144 Solutions
23 Solvers

Last Solution submitted on Mar 27, 2020

Last 200 Solutions

Problem Comments

1 Comment

1 Comment

Paul Berglund on 5 Oct 2014

% this problem is not guaranteed solvable
isequal(spdiags([eye(5) zeros(5)]),spdiags(eye(5)))

Problem Recent Solvers23

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Problem Tags

diag matrix manipulation spdiags

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