Matrix: QLi/largebasis

Description: Large basis matrix from Q. Li, Univ. Wisconsin

QLi/largebasis graph
(undirected graph drawing)

QLi/largebasis

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  • Matrix group: QLi
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  • download as a MATLAB mat-file, file size: 7 MB. Use UFget(1893) or UFget('QLi/largebasis') in MATLAB.
  • download in Matrix Market format, file size: 23 MB.
  • download in Rutherford/Boeing format, file size: 7 MB.

    Matrix properties
    number of rows440,020
    number of columns440,020
    nonzeros5,240,084
    structural full rank?yes
    structural rank440,020
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries320,016
    nonzero pattern symmetrysymmetric
    numeric value symmetry 0%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorQ. Li
    editorT. Davis
    date2008
    kindoptimization problem
    2D/3D problem?no

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD5,040,071
    Cholesky flop count6.1e+07
    nnz(L+U), no partial pivoting, with AMD9,640,122
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD5,440,157
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD9,860,222

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 320016 explicit zero entries.

    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.