Matrix: Grund/b2_ss

Description: Unsymmetric Matrix b2_ss, F. Grund, Dec 1994.

Grund/b2_ss graph Grund/b2_ss graph
(bipartite graph drawing) (graph drawing of A+A')


Grund/b2_ss dmperm of Grund/b2_ss

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  • Matrix group: Grund
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  • download as a MATLAB mat-file, file size: 12 KB. Use UFget(450) or UFget('Grund/b2_ss') in MATLAB.
  • download in Matrix Market format, file size: 18 KB.
  • download in Rutherford/Boeing format, file size: 13 KB.

    Matrix properties
    number of rows1,089
    number of columns1,089
    nonzeros3,895
    structural full rank?yes
    structural rank1,089
    # of blocks from dmperm249
    # strongly connected comp.1
    explicit zero entries333
    nonzero pattern symmetry 1%
    numeric value symmetry 0%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorF. Grund
    editorF. Grund
    date1997
    kindchemical process simulation problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 1089-by-1

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD85,194
    Cholesky flop count1.7e+07
    nnz(L+U), no partial pivoting, with AMD169,299
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD3,895
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD9,864

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 333 explicit zero entries.

    SVD-based statistics:
    norm(A)209350
    min(svd(A))2.73159e-07
    cond(A)7.66404e+11
    rank(A)1,089
    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

    Grund/b2_ss 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.