MiniGallery, Sampler of MATLAB Test Matrices
MATLAB has dozens of test matrices. Here are a few.
Contents
Mini_Gallery
- Random. A = sprand(n,n,0.25). Random sparse, density = 0.25.
- Bucky. A = bucky. Sparse connectivity graph of the geodesic dome, the soccer ball, and the carbon-60 molecule.
- Wilkinson. A = wilkinson(n). Wn+. Nearly equal double eigenvalues.
- Band. A = triu(tril(A,2),-2). Elements near diagonal.
- Triangular. A = triu(A). Elements on and above diagonal.
- Hessenberg. A = triu(A,-1). Upper triangular plus one subdiagonal. See schur.
- Permutation. A = sparse(randperm(n),1:n,1). One +1 in each row and column.
- Companion. c = charpoly(A); A = [-c(2:end); eye(n-1,n)]. Traditional companion matrix.
- Fiedler. c = charpoly(A); A = fiedler(-c(2:end)). Fiedler companion matrix.
- Hankel. A = flip(gallery('toeppd',n)). Constant antidiagonals.
- Toeplitz. A = gallery('toeppd',n). Constant diagonals.
- Magic. A = magic(n). Magic square.
Collections
- gallery. Nick Higham and MathWorks, https://www.mathworks.com/help/matlab/ref/gallery.html
- Anymatrix. Nick Higham and Mantas Mikaitis, https://nhigham.com/2021/11/09/anymatrix>
- SuiteSparse. Tim Davis, Yifan Hu and Scott Kolodzie, http://sparse.tamu.edu
- MatrixMarket, NIST, https://math.nist.gov/MatrixMarket.
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Published with MATLAB® R2023a