Matrix: Schenk_IBMNA/c-21

Description: IBM TJ Watson, non-linear optimization

Schenk_IBMNA/c-21 graph
(undirected graph drawing)


Schenk_IBMNA/c-21 dmperm of Schenk_IBMNA/c-21

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  • Matrix group: Schenk_IBMNA
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  • download as a MATLAB mat-file, file size: 195 KB. Use UFget(1540) or UFget('Schenk_IBMNA/c-21') in MATLAB.
  • download in Matrix Market format, file size: 162 KB.
  • download in Rutherford/Boeing format, file size: 148 KB.

    Matrix properties
    number of rows3,509
    number of columns3,509
    nonzeros32,145
    structural full rank?yes
    structural rank3,509
    # of blocks from dmperm7
    # strongly connected comp.7
    explicit zero entries12
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?no
    positive definite?no

    authorIBM
    editorO. Schenk
    date2006
    kindoptimization problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 3509-by-1

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD34,682
    Cholesky flop count9.1e+05
    nnz(L+U), no partial pivoting, with AMD65,855
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD232,524
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD463,868

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 12 explicit zero entries.

    SVD-based statistics:
    norm(A)5972.28
    min(svd(A))0.00181951
    cond(A)3.28236e+06
    rank(A)3,509
    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

    Schenk_IBMNA/c-21 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.