Matrix: Bai/tols4000

Description: TOLOSA MATRIX

Bai/tols4000 graph Bai/tols4000 graph
(bipartite graph drawing) (graph drawing of A+A')


Bai/tols4000 dmperm of Bai/tols4000
scc of Bai/tols4000

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  • Matrix group: Bai
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  • download as a MATLAB mat-file, file size: 39 KB. Use UFget(1640) or UFget('Bai/tols4000') in MATLAB.
  • download in Matrix Market format, file size: 47 KB.
  • download in Rutherford/Boeing format, file size: 45 KB.

    Matrix properties
    number of rows4,000
    number of columns4,000
    nonzeros8,784
    structural full rank?yes
    structural rank4,000
    # of blocks from dmperm3,983
    # strongly connected comp.3,129
    explicit zero entries0
    nonzero pattern symmetry 36%
    numeric value symmetry 0%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorS. Godet-Thobie
    editorZ. Bai, D. Day, J. Demmel, J. Dongarra
    date1991
    kindcomputational fluid dynamics problem
    2D/3D problem?yes

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD8,577
    Cholesky flop count4.1e+04
    nnz(L+U), no partial pivoting, with AMD13,154
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD6,879
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD11,133

    SVD-based statistics:
    norm(A)2.3445e+07
    min(svd(A))0.995312
    cond(A)2.35554e+07
    rank(A)4,000
    sprank(A)-rank(A)0
    null space dimension0
    full numerical rank?yes

    singular values (MAT file):click here
    SVD method used:s = svd (full (A)) ;
    status:ok

    Bai/tols4000 svd

    For a description of the statistics displayed above, click here.

    Maintained by Tim Davis, last updated 12-Mar-2014.
    Matrix pictures by cspy, a MATLAB function in the CSparse package.
    Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.