Group Andrews

Group Description
Large eigenvalue problem from Stuart Andrews, Brown University, Rhode Island.
stu at

In MATLAB, the problem statement is:

    LL = load('LL.mat');
    L = LL.L;
    opts.tol = 1e-9;
    opts.disp = 5;
    [E,V] = eigs(L, 5, 'sm', opts);

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Stuart Andrews
Brown University, Computer Science, Box 1910, Prov, RI, 02912
stu at
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A large symmetric positive definite matrix, with seemingly random
    sparsity pattern.  LU (using UMFPACK v4.6) fails, because it uses AMD.
    AMD obtains an ordering with nnz(L) of 117,039,940.  METIS gets 36,595,274.
    CHOLMOD's NESDIS gets 37,089,917.  CHOLMOD can solve it with either the
    METIS or NESDIS ordering, but not with AMD (x = cholmod(A,b) works if METIS
    is installed, but not otherwise).
Displaying 1 collection matrix
Id Name Group Rows Cols Nonzeros Kind Date Download File
924 Andrews Andrews 60,000 60,000 760,154 Computer Graphics/Vision Problem 2003 MATLAB Rutherford Boeing Matrix Market